11/2/11 Da\light saving time - Wikipedia, the free enc\clopedia
1/19en.wikipedia.org/wiki/Da\light_saving_time
Although not used by most of the world's people, daylight
saving time is common in the Northern Hemisphere high
latitudes.
DST observed
DST no longer observed
DST never observed
Da\light saving timeFrom Wikipedia, the free encyclopedia
Da\light saving time (DST)also summertime in several countries including in BritishEnglish and European official terminology (seeTerminolog\)is the practice of temporarilyadvancing clocks during the summertime so thatafternoons have more daylight and morningshave less. Typically clocks are adjusted forwardone hour near the start of spring and are
adjusted backward in autumn.[1] Modern DSTwas first proposed in 1895 by George Vernon
Hudson.[2] Many countries have used it sincethen; details vary by location and changeoccasionally.
The practice has been both praised and
criticized.[1] Adding daylight to afternoonsbenefits retailing, sports, and other activities that
exploit sunlight after working hours,[3] but
causes problems for farming, evening entertainment and other occupations tied to the sun.[4][5] Its effect on healthand crime is less clear. Although an early goal of DST was to reduce evening usage of incandescent lighting,
formerly a primary use of electricity,[6] modern heating and cooling usage patterns differ greatly, and research about
how DST currently affects energy use is limited or contradictory.[7]
DST clock shifts present other challenges. They complicate timekeeping, and can disrupt meetings, travel, billing,
recordkeeping, medical devices, heavy equipment,[8] and sleep patterns.[9] Software can often adjust computer
clocks automatically, but this can be limited and error-prone, particularly when DST protocols are changed.[10]
Contents
1 Origin
2 Procedure
3 Dispute over benefits and drawbacks
3.1 Energy use3.2 Economic effects
3.3 Public safety
3.4 Health
3.5 Complexity
4 Politics
5 Terminology
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Franklin's 1784 letter aboutdaylight had neither title nor
byline.[18]
William Willett'spamphlet promoting DSTwent through nineteen
editions.[25]
G.V. Hudson invented
modern DST, proposing it
first in 1895.
When DST starts in
central Europe, clocks
advance from 02:00 CET
to 03:00 CEST.
February 1908.[26] A select committee was set up to examine the issue, butPearce's bill did not become law, and several other bills failed in the followingyears. Willett lobbied for the proposal in the UK until his death in 1915.
Starting on 30 April 1916, Germany and its World War I allies were the first touse DST (German: Sommer]eit) as a way to conserve coal during wartime.Britain, most of its allies, and many European neutrals soon followed suit. Russiaand a few other countries waited until the next year and the United Statesadopted it in 1918. Since then, the world has seen many enactments, adjustments,
and repeals.[27]
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PUocedXUe
See also: Da\light saving time around the world
In a typical case where a one-hour shift occurs at 02:00 local time, in spring theclock jumps forward from the last moment of 01:59 standard time to 03:00 DST andthat day has 23 hours, whereas in autumn the clock jumps backward from the lastmoment of 01:59 DST to 01:00 standard time, repeating that hour, and that day has25 hours. A digital display of local time does not read 02:00 exactly at the shift, butinstead jumps from 01:59:59.9 either forward to 03:00:00.0 or backward to01:00:00.0. In this example, a location observing UTC+10 during standard time is atUTC+11 during DST; conversely, a location at UTC10 during standard time is atUTC9 during DST.
Clock shifts are usually scheduled near a weekend midnight to lessen disruption toweekday schedules. A one-hour shift is customary, but Australia's Lord Howe Island
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When DST ends in
central Europe, clocks
retreat from 03:00 CEST
to 02:00 CET. Other
regions switch at
different times.
In early 2008 central Brazil was one,
two, or three hours ahead of eastern
U.S., depending on the date.
Time zones often lie west of their idealized boundaries, resulting
in year-round DST.
uses a half-hour shift.[28] Twenty-minute and two-hour shifts have been used in thepast.
Coordination strategies differ when adjacent time zones shift clocks. The EuropeanUnion shifts all at once, at 01:00 UTC; for example, Eastern European Time is
always one hour ahead of Central European Time.[29] Most of North America shiftsat 02:00 local time, so its zones do not shift at the same time; for example, MountainTime can be temporarily either zero or two hours ahead of Pacific Time. In the past,Australian districts went even further and did not always agree on start and enddates; for example, in 2008 most DST-observing areas shifted clocks forward on
October 5 but Western Australia shifted on October 26.[30] In some cases only partof a country shifts; for example, in the U.S., Hawaii and most of Arizona do not
observe DST.[31]
Start and end dates vary with location and year. Since 1996 European Summer Timehas been observed from the last Sunday in March to the last Sunday in October;
previously the rules were not uniform across the European Union.[29] Starting in2007, most of the United States and Canada observe DST from the second Sunday in March to the first Sunday in
November, almost two-thirds of the year.[32] The 2007 U.S. change was part of the Energy Policy Act of 2005;previously, from 1987 through 2006, the start and end dates were the first Sunday in April and the last Sunday inOctober, and Congress retains the right to go back to the previous dates now that an energy-consumption study
has been done.[33]
Beginning and ending dates are the reverse in the southern hemisphere.For example, mainland Chile observes DST from the second Saturday inOctober to the second Saturday in March, with transitions at 24:00 local
time.[34] The time difference between the United Kingdom and mainlandChile may therefore be five hours during the Northern summer, threehours during the Northern winter and four hours a few weeks per yearbecause of mismatch of changing dates.
Western China, Iceland, Russia and other areasskew time zones westward, in effect observingDST year-round without complications fromclock shifts. For example, Saskatoon,Saskatchewan, is at 10639 W longitude,slightly west of center of the idealized MountainTime Zone (105 W), but the time inSaskatchewan is Central Standard Time(90 W) year-round, so Saskatoon is always
about 67 minutes ahead of mean solar time.[35]
Conversely, northeast India and a few otherareas skew time zones eastward, in effect
observing negative DST.[36] The United Kingdom and Ireland experimented with year-round DST from 1968 to
1971 but abandoned it because of its unpopularity, particularly in northern regions.[37]
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William Willett
independently
proposed DST in
1907 and advocated
it tirelessly.[40]
Western France, Spain, and other areas skew time zones and shift clocks, in effect observing DST in winter with anextra hour in summer. For example, Nome, Alaska, is at 16524 W longitude, which is just west of center of theidealized Samoa Time Zone (165 W), but Nome observes Alaska Time (135 W) with DST, so it is slightly more
than two hours ahead of the sun in winter and three in summer.[38] Double daylight saving time has been used on
occasion; for example, Britain used it during World War II.[29]
DST is generally not observed near the equator, where sunrise times do not vary enough to justify it. Somecountries observe it only in some regions; for example, southern Brazil observes it while equatorial Brazil does
not.[39] Only a minority of the world's population uses DST because Asia and Africa generally do not observe it.
Dispute over benefits and drawbacks
Willett's 1907 proposal argued that DST increases opportunities for outdoor leisureactivities during afternoon sunlight hours. The longer days nearer the summer solstice inhigh latitudes offer more room to shift daylight from morning to evening so that early
morning daylight is not wasted.[25] DST is commonly not observed during most of winter,because its mornings are darker: workers may have no sunlit leisure time, and children
may need to leave for school in the dark.[41]
General agreement about the day's layout confers so many advantages that a standardDST schedule usually outranks ad hoc efforts to get up earlier, even for people who
personally dislike the DST schedule.[42] The advantages of coordination are so great thatmany people ignore whether DST is in effect by altering their nominal work schedules to
coordinate with television broadcasts or daylight.[43]
Energ\ use
DST's potential to save energy comes primarily from its effects on residential lighting,
which consumes about 3.5% of electricity in the U.S. and Canada.[7] Delaying the nominaltime of sunset and sunrise reduces the use of artificial light in the evening and increases it inthe morning. As Franklin's 1784 satire pointed out, lighting costs are reduced if theevening reduction outweighs the morning increase, as in high-latitude summer when mostpeople wake up well after sunrise. An early goal of DST was to reduce evening usage of incandescent lighting,
formerly a primary use of electricity.[6] Although energy conservation remains an important goal,[36] energy usagepatterns have greatly changed since then, and recent research is limited and reports contradictory results. Electricity
use is greatly affected by geography, climate, and economics, making it hard to generalize from single studies.[7]
The U.S. Dept. of Transportation (DOT) concluded in 1975 that DST might reduce the country's
electricity usage by 1% during March and April,[7] but the National Bureau of Standards (NBS)
reviewed the DOT study in 1976 and found no significant savings.[41]
In 2000 when parts of Australia began DST in late winter, overall electricity consumption did not
decrease, but the morning peak load and prices increased.[44]
In Western Australia during summer 200607, DST increased electricity consumption during hotter days
and decreased it during cooler days, with consumption rising 0.6% overall.[45]
Although a 2007 study estimated that introducing DST to Japan would reduce household lighting energy
consumption,[46] a 2007 simulation estimated that DST would increase overall energy use in Osaka
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residences by 0.13%, with a 0.02% decrease due to less lighting more than outweighed by a 0.15%
increase due to extra cooling; neither study examined non-residential energy use.[47] This is probably
because DST's effect on lighting energy use is mainly noticable in residences.[7]
A 2007 study found that the earlier start to DST that year had little or no effect on electricity
consumption in California.[48]
A 2007 study estimated that winter daylight saving would prevent a 2% increase in average daily
electricity consumption in Great Britain.[49] This paper was revised in October 2009 .[50]
A 2008 study examined billing data in Indiana before and after it adopted DST in 2006, and concluded
that DST increased overall residential electricity consumption by 1% to 4%, due mostly to extra
afternoon cooling and extra morning heating; the main increases came in the fall. The overall annual costof DST to Indiana households was estimated to be $9 million, with an additional $1.75.5 million for
social costs due to increased pollution.[51]
The U.S. Dept. of Energy (DOE) concluded in a 2008 report that the 2007 U.S. extension of DST
saved 0.5% of electricity usage during the extended period.[52] This report analyzed only the extension,
not the full eight months of daylight saving, and did not examine the use of heating fuels.[53]
Several studies have suggested that DST increases motor fuel consumption.[7] The 2008 DOE report found no
significant increase in motor gasoline consumption due to the 2007 U.S. extension of DST.[52]
Economic effects
Retailers, sporting goods makers, and other businesses benefit from extra afternoon sunlight, as it induces
customers to shop and to participate in outdoor afternoon sports.[54] In 1984, ForWXne magazine estimated that aseven-week extension of DST would yield an additional $30 million for 7-Eleven stores, and the National Golf
Foundation estimated the extension would increase golf industry revenues $200 million to $300 million.[55] A 1999
study estimated that DST increases the revenue of the European Union's leisure sector by about 3%.[7] Conversely,
DST can adversely affect farmers and others whose hours are set by the sun.[4] For example, grain harvesting isbest done after dew evaporates, so when field hands arrive and leave earlier in summer their labor is less
valuable.[56] DST also hurts prime-time broadcast ratings,[5] drive-ins and other theaters.[57]
Changing clocks and DST rules has a direct economic cost, entailing extra work to support remote meetings,computer applications and the like. For example, a 2007 North American rule change cost an estimated
$500 million to $1 billion.[58] Although it has been argued that clock shifts correlate with decreased economicefficiency, and that in 2000 the daylight-saving effect implied an estimated one-day loss of $31 billion on U.S. stock
exchanges,[59] the estimated numbers depend on the methodology[60] and the results have been disputed.[61]
Public safet\
In 1975 the U.S. DOT conservatively identified a 0.7% reduction in traffic fatalities during DST, and estimated the
real reduction to be 1.5% to 2%,[62] but the 1976 NBS review of the DOT study found no differences in traffic
fatalities.[41] In 1995 the Insurance Institute for Highway Safety estimated a reduction of 1.2%, including a 5%
reduction in crashes fatal to pedestrians.[63] Others have found similar reductions.[64] Single/Double Summer Time(SDST), a variant where clocks are one hour ahead of the sun in winter and two in summer, has been projected to
reduce traffic fatalities by 3% to 4% in the UK, compared to ordinary DST.[65] It is not clear whether sleep
disruption contributes to fatal accidents immediately after the spring clock shifts.[66] A correlation between clock
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The William Willett Memorial
Sundial is always on DST.
Russia to stay in DST all year long. Officials at the time talked about an annual increase in suicides.[84]
Comple[it\
DST's clock shifts have the obvious disadvantage of complexity. People must remember to change their clocks; this
can be time-consuming, particularly for mechanical clocks that cannot be moved backward safely.[85] People whowork across time zone boundaries need to keep track of multiple DST rules, as not all locations observe DST orobserve it the same way. The length of the calendar day becomes variable; it is no longer always 24 hours.Disruption to meetings, travel, broadcasts, billing systems, and records management is common, and can be
expensive.[86] During an autumn transition from 02:00 to 01:00, a clock reads times from 01:00:00 through
01:59:59 twice, possibly leading to confusion.[87]
Damage to a German steel facility occurred during a DST transition in 1993,when a computer timing system linked to a radio time synchronization signalallowed molten steel to cool for one hour less than the required duration, resulting
in spattering of molten steel when it was poured.[8] Medical devices may generateadverse events that could harm patients, without being obvious to clinicians
responsible for care.[88] These problems are compounded when the DST rulesthemselves change; software developers must test and perhaps modify manyprograms, and users must install updates and restart applications. Consumersmust update devices such as programmable thermostats with the correct DST
rules, or manually adjust the devices' clocks.[10]
Some clock-shift problems could be avoided by adjusting clocks continuously[89]
or at least more gradually[90]for example, Willett at first suggested weekly 20-minute transitionsbut this would add complexity and has never beenimplemented.
DST inherits and can magnify the disadvantages of standard time. For example,when reading a sundial, one must compensate for it along with time zone and
natural discrepancies.[91] Also, sun-exposure guidelines like avoiding the sun within two hours of noon become less
accurate when DST is in effect.[92]
Politics
Daylight saving has caused controversy since it began.[1] Winston Churchill argued that it enlarges "the opportunities
for the pursuit of health and happiness among the millions of people who live in this country"[93] and pundits have
dubbed it "Daylight Slaving Time".[94] Historically, retailing, sports and tourism interests have favored daylightsaving, while agricultural and evening entertainment interests have opposed it, and its initial adoption had been
prompted by energy crisis and war.[95]
The fate of Willett's 1907 proposal illustrates several political issues involved. The proposal attracted manysupporters, including Balfour, Churchill, Lloyd George, MacDonald, Edward VII (who used half-hour DST atSandringham), the managing director of Harrods, and the manager of the National Bank. However, the oppositionwas stronger: it included Prime Minister Asquith, Christie (the Astronomer Royal), George Darwin, Napier Shaw(director of the Meteorological Office), many agricultural organizations, and theater owners. After many hearings
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11/2/11 Da\light saving time - Wikipedia, the free enc\clopedia
11/19en.wikipedia.org/wiki/Da\light_saving_time
A 2001 U.S. public service
advertisement reminded
people to adjust clocks
manually.
updates are installed as part of ordinary system maintenance. In Unix-like systemsthe TZ environment variable specifies the location name, as inT Z = ' A m e r i c a / N e Z _ Y o r k ' . On Linux however there is a system-wide setting
that is applied if the TZ environment variable isn't set, this setting is controlled bythe contents of the /etc/localtime file, which is usually a symlink or hardlink to oneof the zoneinfo files. Internal time is stored in timezone-independent epoch time;the TZ is used by each of potentially many simultaneous users and processes toindependently localize time display.
Older or stripped-down systems may support only the TZ values required byPOSIX, which specify at most one start and end rule explicitly in the value. Forexample, T Z = ' E S T 5 E D T , M 3 . 2 . 0 / 0 2 : 0 0 , M 1 1 . 1 . 0 / 0 2 : 0 0 ' specifies time for
eastern North America starting in 2007. TZ must be changed whenever DSTrules change, and the new TZ value applies to all years, mishandling some older
time stamps.[121]
Microsoft WindoZs
As with zoneinfo, a user of Microsoft Windows configures DST by specifying thename of a location, and the operating system then consults a table of rule sets that must be updated when DST ruleschange. Procedures for specifying the name and updating the table vary with release. Updates are not issued for
older versions of Microsoft Windows.[122] Windows Vista supports at most two start and end rules per time zonesetting. In a Canadian location observing DST, a single Vista setting supports both 19872006 and post-2006 timestamps, but mishandles some older time stamps. Older Microsoft Windows systems usually store only a single start
and end rule for each zone, so that the same Canadian setting reliably supports only post-2006 time stamps.[123]
These limitations have caused problems. For example, before 2005, DST in Israel varied each year and wasskipped some years. Windows 95 used rules correct for 1995 only, causing problems in later years. In Windows98 Microsoft marked Israel as not having DST, forcing Israeli users to shift their computer clocks manually twice ayear. The 2005 Israeli Daylight Saving Law established predictable rules using the Jewish calendar but Windowszone files cannot represent the rules' dates in a year-independent way. Partial workarounds, which mishandle older
time stamps, include manually switching zone files every year[124] and a Microsoft tool that switches zones
automatically.[125]
Microsoft Windows keeps the system real-time clock in local time. This causes several problems, includingcompatibility when multi booting with operating systems that set the clock to UTC, and double-adjusting the clockwhen multi booting different Windows versions, such as with a rescue boot disk. This approach is a problem evenin Windows-only systems: there is no support for per-user timezone settings, only a single system-wide setting. In2008 Microsoft hinted that future versions of Windows will partially support a Windows registry entryRealTimeIsUniYersal that had been introduced many years earlier, when Windows NT supported RISC machines
with UTC clocks, but had not been maintained since.[126]
An interesting effect can be observed with file time properties. The NTFS file system used by recent versions ofWindows stores the file with a UTC time stamp, but displays it corrected to localor seasonaltime. However,the FAT filesystem commonly used on removable devices stores only the local time. Consequently, when a file iscopied from the hard disk onto separate media, its time will be set to the current local time. If the time adjustment ischanged, perhaps automatically (daylight saving) or if the user selects a different time zone, then when the
11/2/11 Da\light saving time - Wikipedia, the free enc\clopedia
12/19en.wikipedia.org/wiki/Da\light_saving_time
timestamps of the original file and the copy are compared there will be a difference. This may be verified (withouthaving to wait for the next equinox) by copying a file, removing the media, adjusting the time zone options,reconnecting the media, and viewing the details of the file and its copy. The same effect can be observed whencompressing and uncompressing files with some file archivers. This effect needs to be in mind when trying todetermine if a file is a duplicate of another although there are other methods of comparing files for equality like usingcheck sums algorithms.
See alVo
Daylight saving time by country
NoWeV
1. ^D E F DST practices and controversies:Michael Downing. SpUing FoUZaUd: The AnnXal MadneVV of Da\lighW SaYing Time. Shoemaker &Hoard; 2005. ISBN 1-59376-053-1.David Prerau. Sei]e Whe Da\lighW: The CXUioXV and ConWenWioXV SWoU\ of Da\lighW SaYing Time.Thunders Mouth Press; 2005. ISBN 1-56025-655-9. The British version, focusing on the UK, isSaYing Whe Da\lighW: Wh\ We PXW Whe ClockV FoUZaUd. Granta Books; ISBN 1-86207-796-7.
2. ^D E George Gibbs. DicWionaU\ of NeZ Zealand BiogUaph\. 2007-06-22. Hudson, George Vernon 18671946(http://www.dnzb.govt.nz/dnzb/default.asp?Find_Quick.asp?PersonEssay=3H42) .
3. ^D E F James C. Benfield. Statement to the U.S. House, Committee on Science, Subcommittee on Energy. In:EneUg\ ConVeUYaWion PoWenWial of E[Wended and DoXble Da\lighW SaYing Time(hWWp://commdocV.hoXVe.goY/commiWWeeV/Vcience/hV\73325.000/hV\73325_0.HTM) . 2001-05-24. (Serial 107-30).
4. ^D E Effect on those whose hours are set by the sun:SpUing FoUZaUd. p. 1933.Sei]e Whe Da\lighW. p. 103110, 149151, 198.
5. ^D E Rick Kissell. Daylight-saving dock ratings (http://www.variety.com/article/VR1117961488.html?categoryid=1275&cs=1) . VaUieW\. 2007-03-20.
6. ^D E Roscoe G. Bartlett. Statement to the U.S. House, Committee on Science, Subcommittee on Energy. In:EneUg\ ConVeUYaWion PoWenWial of E[Wended and DoXble Da\lighW SaYing Time(hWWp://commdocV.hoXVe.goY/commiWWeeV/Vcience/hV\73325.000/hV\73325_0.HTM) . 2001-05-24. (Serial 107-30).
7. ^D E F G H I J Myriam B.C. Aries; Guy R. Newsham. Effect of daylight saving time on lighting energy use: aliterature review (http://www.nrc-cnrc.gc.ca/obj/irc/doc/pubs/nrcc49212/nrcc49212.pdf) [PDF]. EneUg\ Polic\.2008;36(6):18581866. doi:10.1016/j.enpol.2007.05.021 (http://dx.doi.org/10.1016%2Fj.enpol.2007.05.021) .
8. ^D E Peter G. Neumann. CompXWeU-RelaWed RiVkV. AddisonWesley; 1994. ISBN 0-201-55805-X. Computer dateand time problems (http://www.csl.sri.com/users/neumann/cal.html#DatesTimes) .
9. ^D E Tuuli A. Lahti; Sami Leppmki; Jouko Lnnqvist; Timo Partonen. Transitions into and out of daylight savingtime compromise sleep and the restactivity cycles (http://www.biomedcentral.com/1472-6793/8/3) . BMCPh\Violog\. 2008;8:3. doi:10.1186/1472-6793-8-3 (http://dx.doi.org/10.1186%2F1472-6793-8-3) . PMID18269740. PMC 2259373 (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2259373/) .
10. ^D E Stephen Tong; Joseph Williams. Are you prepared for daylight saving time in 2007? IT PUofeVVional.2007;9(1):3641. doi:10.1109/MITP.2007.2 (http://dx.doi.org/10.1109%2FMITP.2007.2) .
11. ^ Berthold. Daylight saving in ancient Rome. The ClaVVical JoXUnal. 1918;13(6):450451.
12. ^ Jrme Carcopino. Dail\ Life in AncienW Rome: The People and Whe CiW\ aW Whe HeighW of Whe EmpiUe. YaleUniversity Press; 1968. ISBN 0-300-00031-6. The days and hours of the Roman calendar.
13. ^ Robert Kaplan. The holy mountain. AWlanWic. 2003;292(5):138141.
14. ^ Hertzel Hillel Yitzhak. T]el HeHaUim: T]iW]iW. Nanuet, NY: Feldheim; 2006. ISBN 1-58330-292-1. When to recite
11/2/11 Da\light saving time - Wikipedia, the free enc\clopedia
13/19en.wikipedia.org/wiki/Da\light_saving_time
14. A Hertzel Hillel Yitzhak. T]el HeHaUim: T]iW]iW. Nanuet, NY: Feldheim; 2006. ISBN 1-58330-292-1. When to recitethe blessing. p. 5358.
15. A Manser, Martin H. (2007). "The Facts on File dictionary of proverbs" (http://books.google.co.uk/books?id=fgaUQc8NbTYC&pg=PA70) . Infobase Publishing. p. 70. http://books.google.co.uk/books?id=fgaUQc8NbTYC&pg=PA70. Retrieved 26 October 2011.
16. A Benjamin Franklin, William Temple Franklin, William Duane (1834). "Memoirs of Benjamin Franklin"(http://books.google.co.uk/books?id=EYiyAAAAIAAJ&pg=PA477) . M'Carty & Davis. p. 477.http://books.google.co.uk/books?id=EYiyAAAAIAAJ&pg=PA477. Retrieved 26 October 2011.
17. A Seymour Stanton Block. Benjamin Franklin: America's inventor (http://www.historynet.com/benjamin-franklin-americas-inventor.htm) . AmeUican HiVWoU\. 2006.
18. ^D E Benjamin Franklin, writing anonymously. Aux auteurs du Journal. JoXUnal de PaUiV. 1784-04-26;(117):511513. French. Its first publication was in the journal's "conomie" section, in a French translation of the Englishoriginal. The revised English version (http://www.webexhibits.org/daylightsaving/franklin3.html) [cited 2009-02-13] is commonly called "An Economical Project", a title that is not Franklin's; see A.O. Aldridge. Franklin's essayon daylight saving. AmeUican LiWeUaWXUe. 1956;28(1):2329. doi:10.2307/2922719(http://dx.doi.org/10.2307%2F2922719) .
19. A Eviatar Zerubavel. The standardization of time: a sociohistorical perspective. The AmeUican JoXUnal of Sociolog\.1982;88(1):123. doi:10.1086/227631 (http://dx.doi.org/10.1086%2F227631) .
20. A G. V. Hudson. On seasonal time-adjustment in countries south of lat. 30(http://rsnz.natlib.govt.nz/volume/rsnz_28/rsnz_28_00_006110.html) . TUanVacWionV and PUoceedingV of Whe NeZZealand InVWiWXWe. 1895;28:734.
21. A G. V. Hudson. On seasonal time (http://rsnz.natlib.govt.nz/volume/rsnz_31/rsnz_31_00_008570.html) .TUanVacWionV and PUoceedingV of Whe NeZ Zealand InVWiWXWe. 1898;31:577588.
22. A New Zealand time. NeZ Zealand GeogUapheU. 1948;4(1):104. doi:10.1111/j.1745-7939.1948.tb01515.x(http://dx.doi.org/10.1111%2Fj.1745-7939.1948.tb01515.x) .
23. A National Maritime Museum. 100 years of British Summer Time (http://www.nmm.ac.uk/explore/astronomy-and-time/time-facts/british-summer-time/) ; 2008.
24. A Sei]e Whe Da\lighW. p. 3.
25. ^D E F Willett pamphlet:William Willett. The ZaVWe of da\lighW (hWWp://ZZZ.Zebe[hibiWV.oUg/da\lighWVaYing/ZilleWW.hWml) . 1st ed.1907.William Willett. The ZaVWe of da\lighW(hWWp://ZZZ.peWWVZoodYillage.co.Xk/Da\lighW_SaYingV_William_WilleWW.pdf) [PDF]. 19th ed. 1914.
26. A PaUliamenWaU\ DebaWeV (hWWp://hanVaUd.millbankV\VWemV.com/commonV/1908/feb/12/da\lighW-VaYing-bill#S4V0184P0_19080212_HOC_254) , House of Commons, 12 February 1908, columns 155156.
27. A Sei]e Whe Da\lighW. p. 5189.
28. A Lord Howe Island Tourism Association. Information for visitors (http://www.lordhoweisland.info/important-info.htm) [cited 2009-04-20].
29. ^D E F G Joseph Myers. History of legal time in Britain (http://www.srcf.ucam.org/~jsm28/british-time/) ; 2009-07-17.
30. A Bureau of Meteorology. Implementation dates of daylight saving time within Australia(http://www.bom.gov.au/climate/averages/tables/dst_times.shtml) ; 2009-09-22.
31. A Sei]e Whe Da\lighW. p. 179180.
32. A Tom Baldwin. US gets summertime blues as the clocks go forward 3 weeks early(http://www.timesonline.co.uk/tol/news/world/us_and_americas/article1499835.ece) . The TimeV (London). 2007-03-12.
33. A Energy Policy Act of 2005, Public Law 109-58 110 (http://frwebgate.access.gpo.gov/cgi-bin/getdoc.cgi?dbname=109_cong_public_laws&docid=f:publ058.109) ; 2005-08-08.
34. A Chilean Hydrographic and Oceanographic Service. Historia de la hora oficial de Chile(http://www.horaoficial.cl/horaof.htm) ; 2008-10-01. Spanish.
35. A Institute for National Measurement Standards. Time zones & daylight saving time (http://www.nrc-cnrc.gc.ca/eng/services/inms/time-services/time-zones.html) ; 2009-08-25.
36. ^D E Dilip R. Ahuja; D. P. Sen Gupta; V. K. Agrawal. Energy savings from advancing the Indian Standard Time by
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36. ^D E Dilip R. Ahuja; D. P. Sen Gupta; V. K. Agrawal. Energy savings from advancing the Indian Standard Time byhalf an hour (http://www.ias.ac.in/currsci/aug102007/298.pdf) [PDF]. Current Science. 2007;93(3):298302.
37. A Philip Johnston. Is it time to lighten our darkness? (http://www.telegraph.co.uk/comment/personal-view/3636598/Home-front.html) Dail\ Telegraph. 2007-01-22.
38. A Ned Rozell. Alaska Science Forum. Alaskans double their daylight savings(http://www.gi.alaska.edu/ScienceForum/ASF12/1278.html) ; 1996-03-28.
39. A Time Service Dept., National Observatory, Brazil. Decretos sobre o Horrio de Vero no Brasil(http://pcdsh01.on.br/DecHV.html) ; 2008-09-16. Portuguese.
40. ^D E Sei]e the Da\light. p. 22.
41. ^D E F Mark Gurevitz (2007-03-07). Da\light saving time (http://opencrs.com/document/RS22284/) . Order CodeRS22284. Congressional Research Service. http://opencrs.com/document/RS22284/.
42. A Thomas C. Schelling. Micromotives and Macrobehavior. W. W. Norton; 2006. ISBN 0-393-32946-1. Hockeyhelmets, daylight saving, and other binary choices (http://simson.net/ref/1972/Schelling_Hockey_Helmets.pdf)[PDF].
43. A Daniel S. Hamermesh; Caitlin Knowles Myers; Mark L. Pocock. Cues for timing and coordination: latitude,Letterman, and longitude. Journal of Labor Economics. 2008;26(2):223246. doi:10.1086/525027(http://dx.doi.org/10.1086%2F525027) .
44. A Ryan Kellogg; Hendrik Wolff. Daylight time and energy: evidence from an Australian experiment. Journal ofEnvironmental Economics and Management. 2008;56(3):207220. doi:10.1016/j.jeem.2008.02.003(http://dx.doi.org/10.1016%2Fj.jeem.2008.02.003) . An earlier version is in: Ryan Kellogg; Hendrik Wolff (2007).Does e[tending da\light saving time save energ\? Evidence from an Australian e[periment(http://escholarship.org/uc/item/3d8252zp) . CSEMWP 163. Center for the Study of Energy Markets.http://escholarship.org/uc/item/3d8252zp.
45. A "The facts on electricity consumption and daylight saving"(http://westernpower.com.au/subContent/aboutUs/mediaCentre/mediaReleases/2007/The_facts_on_electricity_consumption_and_Daylight_Saving.html) (Press release). Western Power. 2007-10-31.http://westernpower.com.au/subContent/aboutUs/mediaCentre/mediaReleases/2007/The_facts_on_electricity_consumption_and_Daylight_Saving.html.
46. A Wee-Kean Fong; Hiroshi Matsumoto; Yu-Fat Lun; Ryushi Kimura. Energy savings potential of the Summer Timeconcept in different regions of Japan from the perspective of household lighting. Journal of Asian Architecture andBuilding Engineering. 2007;6(2):371378. doi:10.3130/jaabe.6.371 (http://dx.doi.org/10.3130%2Fjaabe.6.371) .
47. A Yoshiyuki Shimoda; Takahiro Asahia; Ayako Taniguchia; Minoru Mizuno. Evaluation of city-scale impact ofresidential energy conservation measures using the detailed end-use simulation model. Energ\. 2007;32(9):16171633. doi:10.1016/j.energy.2007.01.007 (http://dx.doi.org/10.1016%2Fj.energy.2007.01.007) .
48. A Adrienne Kandel; Margaret Sheridan (2007-05-25) (PDF). The effect of earl\ da\light saving time on Californiaelectricit\ consumption: a statistical anal\sis (http://energy.ca.gov/2007publications/CEC-200-2007-004/CEC-200-2007-004.PDF) . CEC-200-2007-004. California Energy Commission. http://energy.ca.gov/2007publications/CEC-200-2007-004/CEC-200-2007-004.PDF.
49. A Brendan Cronin; Elizabeth Garnsey (2007-10-19) (PDF). Da\light saving in GB; is there evidence in favour ofclock time on GMT? (http://www.eng.cam.ac.uk/news/stories/2007/BSTvGMT/garnsey_gmt_policy_191007.pdf). Dept. of Engineering, University of Cambridge.http://www.eng.cam.ac.uk/news/stories/2007/BSTvGMT/garnsey_gmt_policy_191007.pdf.
50. A Brendan Cronin; Elizabeth Garnsey (2009-10-20) (PDF). Da\light saving in GB; is there evidence in favour ofclock time on GMT? (October 2009 revision)(http://www.ifm.eng.cam.ac.uk/people/ewg/gmt_cronin_garnsey_rev_oct09.pdf) . Dept. of Engineering,University of Cambridge. http://www.ifm.eng.cam.ac.uk/people/ewg/gmt_cronin_garnsey_rev_oct09.pdf.
51. A Matthew J. Kotchen; Laura E. Grant (2008) (PDF). Does da\light saving time save energ\? evidence from anatural e[periment in Indiana (http://www2.bren.ucsb.edu/~kotchen/links/DSTpaper.pdf) . NBER Working PaperNo. 14429. National Bureau of Economic Research. http://www2.bren.ucsb.edu/~kotchen/links/DSTpaper.pdf.Lay summary (http://online.wsj.com/public/article/SB120406767043794825.html) : Wall Street Journal, 2008-02-27.
52. ^D E David B. Belzer; Stanton W. Hadley; Shih-Miao Chin (2008) (PDF). Impact of E[tended Da\light SavingTime on national energ\ consumption: report to Congress, Energ\ Polic\ Act of 2005, Section 110(http://www1.eere.energy.gov/ba/pba/pdfs/epact_sec_110_edst_report_to_congress_2008.pdf) . U.S. Dept. of
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(http://www1.eere.energy.gov/ba/pba/pdfs/epact_sec_110_edst_report_to_congress_2008.pdf) . U.S. Dept. ofEnergy. http://www1.eere.energy.gov/ba/pba/pdfs/epact_sec_110_edst_report_to_congress_2008.pdf.
53. A Michael Downing. Daylight saving: beat the clock (http://www.huffingtonpost.com/michael-downing/daylight-saving-beat-the_b_497851.html) . HXffingWon PoVW. 2010-03-13.
54. A Dana Knight. Daylight-saving time becomes daylight-spending time for many businesses. IndianapoliV SWaU.2006-04-17.
55. A SpUing FoUZaUd. p. 147148.
56. A Daylight savings time (http://www.house.leg.state.mn.us/hinfo/swkly/1995-96/select/time.txt) . SeVVion Weekl\.1991. Minnesota House Public Information Office. "... the MinneapoliV SWaU, Jan. 28, 1959 ... [stated] 'Farmerscomplained that they cannot get into the fields any earlier than under standard time ... because the morning sundoes not dry the dew "on daylight savings time." ' "
57. A Todd D. Rakoff. A Time foU EYeU\ PXUpoVe: LaZ and Whe Balance of Life. Harvard University Press; 2002.ISBN 0-674-00910-X. p. 26.
58. A Ben Arnoldy. Latest computer glitch: daylight saving time (http://www.csmonitor.com/2007/0307/p02s01-stct.html) . ChUiVWian Science MoniWoU. 2007-03-07.
59. A Mark J. Kamstra; Lisa A. Kramer; Maurice D. Levi. Losing sleep at the market: the daylight saving anomaly.AmeUican Economic ReYieZ. 2000;90(4):10051011.
60. A Luisa Mller; Dirk Schiereck; Marc W. Simpson; Christian Voigt. Daylight saving effect. JoXUnal ofMXlWinaWional Financial ManagemenW. 2009;19(2):127138. doi:10.1016/j.mulfin.2008.09.001(http://dx.doi.org/10.1016%2Fj.mulfin.2008.09.001) .
61. A Reinhold P. Lamb; Richard A. Zuber; John M. Gandar. Don't lose sleep on it: a re-examination of the daylightsavings time anomaly. Applied Financial EconomicV. 2004;14(6):443446. doi:10.1080/09603100410001673676(http://dx.doi.org/10.1080%2F09603100410001673676) .
62. A Linda L. Lawson. EneUg\ ConVeUYaWion PoWenWial of E[Wended and DoXble Da\lighW SaYing Time(hWWp://commdocV.hoXVe.goY/commiWWeeV/Vcience/hV\73325.000/hV\73325_0.HTM) . 2001-05-24. (Serial 107-30).Statement to the U.S. House, Committee on Science, Subcommittee on Energy.
63. A Susan A. Ferguson; David F. Preusser; Adrian K. Lund; Paul L. Zador; Robert G. Ulmer. Daylight saving timeand motor vehicle crashes: the reduction in pedestrian and vehicle occupant fatalities(http://ajph.aphapublications.org/cgi/reprint/85/1/92.pdf) [PDF]. AmeUican JoXUnal of PXblic HealWh.1995;85(1):9295. doi:10.2105/AJPH.85.1.92 (http://dx.doi.org/10.2105%2FAJPH.85.1.92) . PMID 7832269.PMC 1615292 (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1615292/) .
64. A Douglas Coate; Sara Markowitz. The effects of daylight and daylight saving time on US pedestrian fatalities andmotor vehicle occupant fatalities. AccidenW Anal\ViV & PUeYenWion. 2003;36(3):351357. doi:10.1016/S0001-4575(03)00015-0 (http://dx.doi.org/10.1016%2FS0001-4575%2803%2900015-0) . PMID 15003579.
65. A J. Broughton; M. Stone (1998). A neZ aVVeVVmenW of Whe likel\ effecWV on Uoad accidenWV of adopWing SDST(http://www.trl.co.uk/online_store/reports_publications/trl_reports/cat_road_user_safety/report_a_new_assessment_of_the_likely_effects_on_road_accidents_of_adopting_sdst.htm) . TRL368. Transport Research Laboratory.http://www.trl.co.uk/online_store/reports_publications/trl_reports/cat_road_user_safety/report_a_new_assessment_of_the_likely_effects_on_road_accidents_of_adopting_sdst.htm.
66. A Alex Vincent; Stanley Coren. Effects of daylight savings time on collision rates. NeZ England JoXUnal ofMedicine. 1998;339(16):11671168. doi:10.1056/NEJM199810153391617 (Full free text)(http://dx.doi.org/10.1056%2FNEJM199810153391617+%28Full+free+text%29) . PMID 9776656. Datasupporting Coren's half of this exchange are in: Stanley Coren. Sleep deficit, fatal accidents, and the spring shift todaylight savings time (http://www.mcmaster.ca/inabis98/occupational/coren0164/) . In: INABIS '98. 1998.
67. A Clock shifts and accidents:Jason Varughese; Richard P. Allen. Fatal accidents following changes in daylight savings time: theAmerican experience. Sleep Medicine. 2001;2(1):3136. doi:10.1016/S1389-9457(00)00032-0(http://dx.doi.org/10.1016%2FS1389-9457%2800%2900032-0) . PMID 11152980.J. Alsousoua; T. Jenks; O. Bouamra; F. Lecky; K. Willett. Daylight savings time (DST) transition: theeffect on serious or fatal road traffic collision related injuries. InjXU\ E[WUa. 2009;40(10):2112.doi:10.1016/j.injury.2009.06.241 (http://dx.doi.org/10.1016%2Fj.injury.2009.06.241) .Tuuli A. Lahti; Jari Haukka; Jouko Lnnqvist; Timo Partonen. Daylight saving time transitions andhospital treatments due to accidents or manic episodes (http://www.biomedcentral.com/1471-2458/8/74) . BMC PXblic HealWh. 2008;8:74. doi:10.1186/1471-2458-8-74
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2458/8/74) . BMC PXblic HealWh. 2008;8:74. doi:10.1186/1471-2458-8-74(http://dx.doi.org/10.1186%2F1471-2458-8-74) . PMID 18302734. PMC 2266740(http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2266740/) .Mats Lambe; Peter Cummings. The shift to and from daylight savings time and motor vehicle crashes.AccidenW Anal\ViV & PUeYenWion. 2000;32(4):609611. doi:10.1016/S0001-4575(99)00088-3(http://dx.doi.org/10.1016%2FS0001-4575%2899%2900088-3) . PMID 10868764.
68. A Christopher M. Barnes; David T. Wagner. Changing to daylight saving time cuts into sleep and increasesworkplace injuries (http://www.apa.org/pubs/journals/releases/apl9451317.pdf) [PDF]. JoXUnal of AppliedPV\cholog\. 2009;94(5):13051317. doi:10.1037/a0015320 (http://dx.doi.org/10.1037%2Fa0015320) . PMID19702372.
69. A House Committee on Energy and Commerce, Subcommittee on Energy Conservation and Power. Da\lighWVaYing Wime. U.S. GPO; 1985-04-24. (Serial No. 99-4). p. 26.
70. A Rachel Pain; Robert MacFarlane; Keith Turner; Sally Gill. 'When, where, if, and but': qualifying GIS and theeffect of streetlighting on crime and fear. EnYiUonmenW and Planning A. 2006;38(11):20552074.doi:10.1068/a38391 (http://dx.doi.org/10.1068%2Fa38391) .
71. A Clock shifts as safety reminders:Helen A.S. Popkin. Changes to daylight-saving time(http://blogs.consumerreports.org/home/2007/03/changes_to_dayl.html) . ConVXmeU RepoUWV Home &YaUd Blog. 2007-03-02.Smoke alarms a burning issue (http://www.stuff.co.nz/auckland/local-news/345066) . EaVW and Ba\VCoXUieU (New Zealand). 2008-04-04."CSPC and USFA encourage consumers to spring forward with fire safety in mind"(http://www.cpsc.gov/cpscpub/prerel/prhtml07/07124.html) (Press release). U.S. Consumer ProductSafety Commission; U.S. Fire Administration. 2007-03-09.http://www.cpsc.gov/cpscpub/prerel/prhtml07/07124.html.American Public Health Association. Get ready: set your clocks, check your stocks(http://getreadyforflu.org/clocksstocks/) ; 2009-02-24.
72. A Debby Golonka. Yahoo Health. Prevent household fires (http://health.yahoo.com/children-resources/prevent-household-fires/healthwise--ue5167.html) ; 2007-03-13.
73. A Sualeh Fatehi. SourceForge.net. Daylight Chart (http://daylightchart.sourceforge.net/) ; 2008.
74. A Michael Rosenberg; Lisa Wood. The power of policy to influence behaviour change: daylight saving and itseffect on physical activity. AXVWUalian and NeZ Zealand JoXUnal of PXblic HealWh. 2010;34(1):8388.doi:10.1111/j.1753-6405.2010.00479.x (http://dx.doi.org/10.1111%2Fj.1753-6405.2010.00479.x) .
75. A A.V. Parisi; J. Turner; D.J. Turnbull; P. Schouten; N. Downs. Influence of summer daylight saving time onscattered erythemal solar ultraviolet exposures. JoXUnal of PhoWochemiVWU\ and PhoWobiolog\ B: Biolog\.2008;91(1):3540. doi:10.1016/j.jphotobiol.2008.01.010 (http://dx.doi.org/10.1016%2Fj.jphotobiol.2008.01.010) .PMID 18321724.
76. A Henry Olders. Average sunrise time predicts depression prevalence. JoXUnal of PV\choVomaWic ReVeaUch.2003;55(2):99105. doi:10.1016/S0022-3999(02)00479-8 (http://dx.doi.org/10.1016%2FS0022-3999%2802%2900479-8) . PMID 12932507.
77. A Shari Roan. Change in daylight saving time may affect moods. LoV AngeleV TimeV. 2007-03-05.
78. ^D E Alex Beam. Dim-witted proposal for daylight time(http://www.boston.com/news/globe/living/articles/2005/07/26/dim_witted_proposal_for_daylight_time/) . BoVWonGlobe. 2005-07-26.
79. A ModeUaWUi[ MXVingV. Daylight savings (http://moderatrix8.blogspot.com/2007/03/daylight-savings.html) ; 2007-03-12. "I now have to drive to work in the dark. This is a real problem for me as I've got terrible night blindnessand avoid driving in the dark at all costs. It's just not safe (especially for the other drivers since I can't tell wherethey are.)"
80. A DST and circadian rhythm:Pablo Valdez; Candelaria Ramrez; Ada Garca. Adjustment of the sleepwake cycle to small (12h)changes in schedule. Biological Rh\Whm ReVeaUch. 2003;34(2):145155.doi:10.1076/brhm.34.2.145.14494 (http://dx.doi.org/10.1076%2Fbrhm.34.2.145.14494) .Thomas Kantermann; Myriam Juda; Martha Merrow; Till Roenneberg. The human circadian clock's
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81. A Michael Berk; Seetal Dodd; Karen Hallam; Lesley Berk; John Gleeson; Margaret Henry. Small shifts in diurnalrhythms are associated with an increase in suicide: the effect of daylight saving. Sleep and Biological Rhythms.2008;6(1):2225. doi:10.1111/j.1479-8425.2007.00331.x (http://dx.doi.org/10.1111%2Fj.1479-8425.2007.00331.x) .
82. A Imre Janszky; Rickard Ljung. Shifts to and from daylight saving time and incidence of myocardial infarction(http://content.nejm.org/cgi/content/full/359/18/1966) . New England Journal of Medicine. 2008;359(18):19661968. doi:10.1056/NEJMc0807104 (http://dx.doi.org/10.1056%2FNEJMc0807104) . PMID 18971502. Laysummary (http://articles.latimes.com/2008/oct/30/science/sci-clocks30) : Los Angeles Times, 2008-10-30.
83. A Nataliya Shirinskikh, translator. Kazakhstan canceled shifting to the 'summer' and 'winter' time(http://engnews.gazeta.kz/art.asp?aid=56924) . Kazakhstan Today. 2005-03-16.
84. A BBC News, 30 Oct. 2011 (http://www.bbc.co.uk/news/world-europe-15512177)
85. A Joey Crandall. Daylight saving time ends Sunday (http://www.recordcourier.com/apps/pbcs.dll/article?AID=/20031024/NEWS/310240104) . RecordCourier. 2003-10-24.
86. A Paul McDougall. PG&E says patching meters for an early daylight-saving time will cost $38 million(http://www.informationweek.com/news/internet/showArticle.jhtml?articleID=197700487) . InformationWeek.2007-03-01.
87. A WebExhibits. Daylight saving time: rationale and original idea (http://www.webexhibits.org/daylightsaving/c.html); 2008. "... Lord Balfour came forward with a unique concern: 'Supposing some unfortunate lady was confinedwith twins ...'"
88. A Daniel G. Schultz. Center for Devices and Radiological Health, Food and Drug Administration. Unpredictableevents in medical equipment due to new daylight saving time change(http://www.fda.gov/MedicalDevices/Safety/AlertsandNotices/PublicHealthNotifications/ucm062068.htm) ; 2007-03-29.
89. A Jesse Ruderman. Indistinguishable from Jesse. Continuous daylight saving time(http://www.squarefree.com/2006/11/01/continuous-daylight-saving-time/) ; 2006-11-01.
90. A Proposal for a finer adjustment of summer time (daylight saving time) (http://jeppesn.dk/summertime.html) ;2011-09-28.
91. A Albert E. Waugh. Sundials: Their Theory and Construction. Dover; 1973. ISBN 0-486-22947-5.
92. A Leith Holloway. Atmospheric sun protection factor on clear days: its observed dependence on solar zenith angleand its relevance to the shadow guideline for sun protection. Photochemistry and Photobiology. 1992;56(2):22934. doi:10.1111/j.1751-1097.1992.tb02151.x (http://dx.doi.org/10.1111%2Fj.1751-1097.1992.tb02151.x) . PMID1502267.
93. A Winston S. Churchill. A silent toast to William Willett. Pictorial Weekly. 1934-04-28.
94. A Seize the Daylight. p. 117.
95. A Seize the Daylight. p. xi.
96. A Seize the Daylight. p. 1224.
97. A Seize the Daylight. p. 7273.
98. ^D E Seize the Daylight. p. 5170.
99. A Seize the Daylight. p. 80101.
100. A Seize the Daylight. p. 103110.
101. A Robert Garland. Ten years of daylight saving from the Pittsburgh standpoint(http://www.clpgh.org/exhibit/dst.html) . Carnegie Library of Pittsburgh; 1927. OCLC 30022847(http://worldcat.org/oclc/30022847) .
102. A Spring Forward. p. 4748.
103. A Seize the Daylight. p. 115118.
104. A David P. Baron. Business and its Environment. 5th ed. Prentice Hall; 2005. ISBN 0-13-187355-5. The politics ofthe extension of daylight saving time.
105. A Seize the Daylight. p. 147155, 175180.
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106. A Ian R. Bartky; Elizabeth Harrison. Standard and daylight-saving time. Scientific American. 1979;240(5):4653.
107. A "1992 Queensland Daylight Saving Referendum" (http://www.ecq.qld.gov.au/WorkArea/linkit.aspx?LinkIdentifier=id&ItemID=74) (PDF). http://www.ecq.qld.gov.au/WorkArea/linkit.aspx?LinkIdentifier=id&ItemID=74. Retrieved 2010-07-25.
108. A "Daylight Saving group launched as new Qld political party"(http://www.abc.net.au/news/stories/2008/12/14/2445953.htm) . ABC News. 2008-12-14.http://www.abc.net.au/news/stories/2008/12/14/2445953.htm. Retrieved 2010-07-25.
109. A "Total Candidates Nominated for Election by Party 2009 State Election"(http://www.ecq.qld.gov.au/elections/state/state2009/results/summary.html#16) . Electoral Commission ofQueensland (ECQ). http://www.ecq.qld.gov.au/elections/state/state2009/results/summary.html#16. Retrieved2010-06-19.
110. A Paige Taylor. Daylight saving at a sunset out west (http://www.theaustralian.com.au/news/nation/daylight-saving-at-a-sunset-out-west/story-e6frg6pf-1225713080046) . The Australian. 2009-05-18.
111. A "Daylight Saving for South East Queensland Referendum Bill 2010"(http://www.legislation.qld.gov.au/Bills/53PDF/2010/DaySavSEQRB10_P.pdf) . 14 April 2010.http://www.legislation.qld.gov.au/Bills/53PDF/2010/DaySavSEQRB10_P.pdf. Retrieved 2010-07-25.
112. A "Daylight saving silence 'deafening'" (http://www.brisbanetimes.com.au/queensland/daylight-saving-silence-deafening-20110616-1g4k6.html) . 16 June 2011. http://www.brisbanetimes.com.au/queensland/daylight-saving-silence-deafening-20110616-1g4k6.html. Retrieved 2011-06-19.
113. A Royal Society for the Prevention of Accidents. Single/Double Summer Time policy paper(http://www.rospa.com/roadsafety/info/summertime_paper2006v2.pdf) [PDF]; October 2006.
114. A Seize the Daylight. p. xv.
115. A Daylight saving time and its variants:Richard A. Meade. Language change in this century. English Journal. 1978;67(9):2730.doi:10.2307/815124 (http://dx.doi.org/10.2307%2F815124) .daylight-saving time (http://education.yahoo.com/reference/dictionary/entry/daylight-saving%20time) .In: Joseph P. Pickett et al., editors. The American Heritage Dictionary of the English Language. 4thed. Boston: Houghton Mifflin; 2000. ISBN 0-395-82517-2. "or daylight-savings time"MerriamWebster's Online Dictionary. "called also daylight saving, daylight savings, daylight savingstime, daylight time" daylight saving time (http://www.merriam-webster.com/dictionary/daylight+saving+time) . [cited 2009-02-13].15 U.S.C. 260a notes (http://www.law.cornell.edu/uscode/html/uscode15/usc_sec_15_00000260---a000-notes.html) [cited 2007-05-09]. "Congressional Findings; Expansion of Daylight Saving Time"
116. A Brent Hopkins. Spring ahead? that's so last year. On Sunday, we will all ... march forward. Is this a good thing?That all depends(http://www.thefreelibrary.com/SPRING+AHEAD%3f+THAT%27S+SO+LAST+YEAR.+ON+SUNDAY%2c+WE+WILL+ALL+...+MARCH...-a0160458551) . Los Angeles Daily News. 2007-03-10.
117. A Steve Lohr. Time change a 'mini-Y2K' in tech terms(http://www.nytimes.com/2007/03/05/technology/05daylight.html) . New York Times. 2007-03-05.
118. A A. Gut; L. Miclea; Sz. Enyedi; M. Abrudean; I. Hoka. Database globalization in enterprise applications. In: 2006IEEE International Conference on Automation, Quality and Testing, Robotics. 2006. p. 356359.
119. A Paul Eggert; Arthur David Olson. Sources for time zone and daylight saving time data(http://www.twinsun.com/tz/tz-link.htm) ; 2008-06-30.
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123. A Microsoft Corp. Visual Studio and daylight saving time change (http://msdn.microsoft.com/en-us/vstudio/bb264729.aspx) ; 2007.
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126. ^ Markus Kuhn. Computer Laboratory, University of Cambridge. IBM PC Real Time Clock should run in UT(http://www.cl.cam.ac.uk/~mgk25/mswish/ut-rtc.html) ; 2009-02-10.
E[ternal links
Daylight Saving Time (http://www.webexhibits.org/daylightsaving/) general history and anecdotes
Saving Time, Saving Energy (http://energy.ca.gov/daylightsaving.html) North American viewpointSummer Time (http://www.merlyn.demon.co.uk/uksumtim.htm) European viewpoint
Sources for time zone and daylight saving time data (http://www.twinsun.com/tz/tz-link.htm) technicalresourcesGraphical Display of Time Differences with Daylight Saving Time (DST) Changes (http://www.daylight-savings-time.info)ITU LEGAL TIME 2011 (http://www.itu.int/dms_pub/itu-t/opb/sp/T-SP-LT.1-2011-PDF-E.pdf)Information about the Current Daylight Saving Time (DST) Rules (http://www.nist.gov/pml/div688/dst.cfm) ,U.S. National Institute of Standards and Technology (NIST.gov)
When Daylight Saving Time begins in 2011 (United States)(http://www.abcactionnews.com/dpp/news/national/when-daylight-saving-time-begins-in-2011)
Countries and territories operating Daylight Saving Time (2010/2011)(http://www.worldtimezone.com/daylight.html)
Retrieved from "http://en.wikipedia.org/w/index.php?title=Daylight_saving_time&oldid=458459750"
Categories: Daylight saving time
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