Overview of Linking: DOI and CrossRef

2002 NFAIS Annual Conference

NFAIS/NISO Linking Workshop

February 24, 2002

Philadelphia

Edward Pentz

Executive Director

CrossRef

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What is CrossRef?

• An independent, non-profit membership organization for ‘pre-competitive’ cooperation

• A cross-publisher network for article-level linking based on DOIs

• IDF Registration Agency– There are now four DOI registration agencies, but CrossRef is the

only one whose mission is to implement citation linking and serve the scholarly community

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Key benefits of the CrossRef/DOI system

• One process - reduces technology problem• No bilateral linking agreements needed

» An agreement with CrossRef is a linking agreement with all CrossRef publishers

• A DOI link is a persistent link, unlike a URL» No stale links in citations or database records.

Publishers can update URLs in one location» Interoperability – ISSNs, ISBNs, SICIs, PIIs

• Infrastructure for standardized metadata and services

• Publishers maintain their own business models while adding value to content

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What does CrossRef do?• Uses DOI system to make linking to full

text scholarly journal articles efficient, manageable, and reliable– Links are between online journals, from

secondary database records and from library pages

– Outbound links: add end-user utility to content– Inbound links: bring more users to content

– Mission: to be the complete citation linking backbone for all scholarly literature in electronic form

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Who is CrossRef?

• CrossRef is a collaborative, non-profit, independent membership organization that employs open standards

• Members: Any publisher of original scholarly material in electronic form

• Libraries: Enrich online catalogues with outgoing links to full text, and increase use of digital archives with incoming links.

• Affiliates and agents: Secondary publishers and journal hosting services are enhancing their products with DOI-based citation links.

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Participants

• Libraries: Max Planck Institute, Stuttgart; KAIST (Korea Advanced Institute of Science Technology), Boston College

• Affiliates: Maruzen, Cambridge Scientific Abstracts, Dialog, IFIS (International Food Information Service), Fiz Karlsruhe, reviews.com, Swets Blackwell, KINS (Korea Info-New Service), EBSCO

• Agents: Allen Press, BioOne, American Institute of Physics, Catchword/ingenta, HighWire, MetaPress

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How does CrossRef work?

• Publishers deposit metadata (in XML) for online articles with CrossRef, including a DOI and URL

• Members and affiliates then query the central metadata database to find the DOI matching the reference from which they want to create a link

• If there is a match, they retrieve the DOI and add it to their electronic record ...

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How does CrossRef work?

• In an online article, a researcher sees and clicks the DOI link (it may say “CrossRef” or just “Article”)

• The DOI resolves to the URL registered by the publisher– terms of access to the full text are set by the publisher

-- in most cases, if the user is entitled to access, she goes straight to the full text of the article

– Most publishers take non-subscribers to the abstract

• Full bibliographic citation and information on getting the article at a minimum

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http://dx.doi.org/10.1006/jmbi.1995.0238

DOI Directory Prefix Suffix

http://www.idealibrary.com/links/doi/10.1006/jmbi.1995.0238

Online article at Publisher “A” website

End User

DOI Directory (Handle System)

Online article at Publisher “B” website

1. User reads Publisher A journal article

2. User clicks on DOI reference link

3. URL/location returned

4. User accesses cited article atPublisher B website

Citation linking using DOIs

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Is it working?

YES!• 102 member publishers, and 40 library or other

affiliates• More than 5,000 journals in the system• Over 4.3 million articles registered• More than 80% of the publishers are currently

depositing and 40% retrieving• 600,000 – 700,000 DOI resolutions per month • 500,000 – 1 million articles per year

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Summary: Advantages of Using DOI

• Persistent identifier• You only update your own URL changes in one

location • External links easier - no need to update• Works across platforms and content types• Permits enhanced linking

– OpenURL-aware Localized Linking– Parameter Passing using OpenURL syntax– Multiple resolution

• URLs are a dead end– IDEAL ScienceDirect

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Next Steps

• Expansion of content types– conference proceedings and reference works

– enable citation linking and drive traffic to, and sales of, proceedings papers and book chapters.

• Parameter Passing– Extra information sent along with a DOI

– (1) track originating journal (2) customize response pages (3) add return buttons, (4) institute special trading rules

– OpenURL will be used for CrossRef parameters

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Parameter Example

• [ Referent ] Bergelson, J. 1997. Isolation of a common receptor for coxsackie B viruses and adenoviruses 2 and 5. Science. (275) 1320-1323. <doi:10.1126/science.275.5304.1320>

•  [ Referring-Entity ] McArthur, James G. et al. 2001. p27-p16 Chimera: A Superior Antiproliferative for the Prevention of Neointimal Hyperplasia. Molecular Therapy. 3(1). <doi:10.1006/mthe.2000.0239>

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http://dx.doi.org/resolve? & ref_id = doi:10.1126/science.275.5304.1320 & rfr_id = dns:crossref.org:idealibrary.com & rfe_id = doi:10.1006/mthe.2000.0239 & rfe_id = issn:1525-0016 & adm_ver = 1.0 & adm_tim = 2002-02-20T14:20:03Z & adm_pid = cr_setver , 01 ; cr_encrypt , cx1Dk0f1ud58jlKfdsAifhe23swkHG^s ; cr_saltver , 01 ; cr_tstamp , 20020220142003 ; cr_orig , idealibrary.com ; cr_origDOI , 10.1006/mthe.2000.0239 ; cr_retURL , http://www.idealibrary.com/links/doi/10.1006/mthe.2000.0239/ref ; cr_retURLtext , Click Here ; cr_doctype , html ; cr_title , Molecular Therapy ; cr_pub , Academic Press ;

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Multiple resolution

• What: A single DOI associated with many possible actions

• What for: Could include (1) multiple URLs for dispersed mirror sites, (2) pointer to a metadata record, (3) access to sub-parts of an article, such as abstract or references only, (4) email address, (5) different versions (“get html” or “get pdf”), (5) author bio, (6) rights information, etc…

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Multiple Resolution for Journals and Conference Proceedings

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CrossRef and Standards

• Guidelines for DOIs in citations, online and print journals– DOIs will be required for primary and secondary

resources

• DOIs for journal titles, books and other types of material

• ONIX/ONIX for Serials– Standardized metadata for exchange of information

– No one format will server all purposes – mapping is necessary

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Conclusion

• Power of collaboration and network effects

• Identifiers and standards (XML, DOI, OpenURL, ONIX)

• Publishers cooperated and moved quickly– Libraries, secondaries and agents now actively

involved

• Continued collaboration needed to improve the scholarly communication process

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the central source for reference linking

don’t be the missing link

http://www.crossref.org

Ed Pentz

epentz@crossref.org