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CITATION LINKING AND THE E-JOURNAL LANDSCAPE. April, 2000. BACKGROUND ASSUMPTIONS. Linking is a core function, not an incidental add-on. The web environment is built around easy navigation between related digital resources. If an information resource is not accessible
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CITATION LINKING AND THE E-JOURNAL LANDSCAPE April, 2000
BACKGROUND ASSUMPTIONS Linking is a core function, not an incidental add-on. The web environment is built around easy navigation between related digital resources. If an information resource is not accessible through links, its value decreases.
E-JOURNALS AND LINKING • Journal literature is almost a poster child for for web-linking • Through citations one traces the “web” of thought on a subject • The value of an e-journal system will depend on its participation in the inter-linked e-journal environment
WHAT WE ARE TRYING TO ACCOMPLISH Any old system Citation Citation LINK CLICK LINK MAGIC Cited Article
WHAT MAKES MAGIC HAPPEN? • Somehow “any old system” must get a useable link into the citations it delivers • Currently there are 2 major approaches to creating links • “algorithmic” • “name-based”
ALGORITHMIC LINK CREATION • Links are built by knowing how to predict the URL for a specific journal article • Link-builder parses citations to determine title, volume, and page information for use in URL • Link-builder knows URL format for each journal title and access system • Dominant mode of creating links today • Used by ISI, Ovid, SilverPlatter, etc • S-Link-S product helps build links
ALGORITHMIC LINK ISSUES • Not every site has algorithmically predictable URLs • How many algorithms do you need? • How many systems need to build algorithms? • High maintenance because of constant change • Does this scale???
NAME-BASED LINKS • Each article is given a unique identifier • Database available to provide identifier look-up from citation data • Either manually or by computer program • Done ahead of time by systems providing links • At the time of use, the identifier is converted into an address through a “resolution server” • DOI is prime example today
FROM DOI TO ARTICLE Any old system Step 1 Citation Search response DOI Step 2 DOI DOI Resolver URL Repository URL Step 3 Cited article Article
“NAMING” IS A POWERFUL SOLUTION • Instead of a vast number of algorithms, a small number of places to look-up links • Linked-to resources can freely move about without breaking links scattered across many systems
BUT -- WHAT IF MORE THAN 1 COPY EXISTS? • Elsevier journals, for example, are available from • Elsevier ScienceDirect • OhioLink • University of Toronto
WHICH URL? DOI Handle Server URL? Sciencedirect.com? Ohiolink.edu? Utoronto.ca?
A PROBLEM • DOI today cannot resolve to more than 1 copy • DOIs have been devised specifically for publisher use in selling electronic publications on the net • They currently resolve to only the publisher’s address!
CROSSREF • CrossRef is largely based on the DOI • Major service is to provide a citation-information-to-DOI look-up service • Should generate a rich set of links between e-journal articles • But…it will only work for publisher’s copy! • OhioLink and Toronto users will get links to Science Direct, not to local copies
THE APPROPRIATE COPY • When more than 1 copy exists, specific populations have the right to access specific copies • Some systems today can do this sort of linking (ISI), but it must be done by EVERY system from which links can come to work properly • Today, only a few systems do this -- can we expect every journal publisher to do this for every subscriber?
WHY MULTIPLE COPIES WILL OCCUR • “Local loading” • A number of institutions are already loading e-journals for their local populations • OhioLink, Toronto, University of Illinois... • Aggregators • Most electronic journal access in many institutions today is through aggregators • OCLC EJO, EBSCO, Ovid, IAC, Bell & Howell
WHY MULTIPLE COPIES (continued) • Mirror sites??? • Which mirror you should use can depend on “where” you are on the net • Some universities have had trouble getting the appropriate mirror site configured • Alternate “free with subscription”copies • Elsevier has alternate sites from ScienceServer for these...
WHY MULTIPLE COPIES (continued) • E-print archives • A lot of current interest in building subject-specific e-print collections (which include published articles) • LANL, PubMedCentral, (CDL, Cornell, MIT...) • Archiving • Institutional failure is as great a danger as technological failure, • Multiple copies held by different parties is the best protection
WILL THE ENVIRONMENT BE CONSTRAINED? • A generalized link-from-anywhere-to- anywhere solution will allow the e-journal environment to evolve naturally • We are in a period of much necessary experimentation • Who are the players? • What are their roles? • How many options will libraries have? • Too early to constrain the options!!!
CURRENT DLF INITIATIVE • Group approach to CrossRef (and now DOI Foundation) on this issue • Many examples of content legally available to our populations that will not be linked-to in the current CrossRef/DOI infrastructures • Have offered to help explore solutions, and to serve as test-beds when appropriate
ICOLC IMPLICATIONS It is IMPORTANT that libraries (and consortia!) let publishers know that they CARE about robust linking!