Our experience with linking and CrossRef Jerry Cowhig, Managing Director Terry Hulbert, Business Development Manager Institute of Physics Publishing CrossRef annual meeting, Boston 25 September 2002

Terry Hulbert

Introduction l Development of linking at IOP l Other electronic developments at IOP l CrossRef experiences l Future linking developments

Linking at IOP all 35 IOP journals on www Hypercite Refs link to INSPEC abs on IOP server Forward citations to IOP papers only “Distributed publishing” Bilateral links AIP, APS, Springer etc STACKS linking protocol Axiom (secondary dbase) INSPEC, later Compendex Links to full text

Linking at IOP (cont) final bilaterals, AP… getting close to total available coverage in physics

AND THEN ALONG CAME... CrossRef

1999 Frankfurt STM: “Linking good”! Sudden announcement, NY Times IOP not in original 12 disciples Online 1999: joined asap Still pursued bilaterals: Elsevier NO!

October 1998

CrossRef June 2000 CrossRef launched Elsevier No to all bilaterals From the start IOP has been a member Elsevier was a major factor for IOP

History post 2000 Bilaterals, CrossRef & other links co-exist SFX and Open URL ZBLSA DOI Forward citations (3rd party)

DOI We use and support because of CrossRef IOP articles all have DOI since 2000 Now also published in print and online Anyone incoming can use our DOIs Linking from IOP: If no bilateral, check for DOI in INSPEC If DOI, we create URL to link directly If no luck, go to CrossRef We are not a member of the IDF

Forward citations To see “who has cited this paper” IOP had this since 1997, Hypercite Now making bilaterals IPAP agreed Verbal agreements with APS, ADS Role for CrossRef

Other IOP electronic initiatives Free first 30 days and other free accesses Archive back to 1874 Local loading Now can include XML reference data Usage stats - COUNTER and more Vivisimo

Current state: Inbound linking (to get IOP text) l Reference intra-linking in EJs - backwards & forwards (Hypercite) l Primary publishers - bilateral agreements, CrossRef l Or STACKS - no contract needed! l Secondary publishers, aggregators, gateways, etc. l Local holdings, OPACs, etc. l Help yourself!! l Docdel PPV: Ingenta, Infotrieve (contract)

Current: Outbound (from IOP to get other text) l Links to primary data, publishers l Links to secondary services eg ChemPort, MathSciNet l Links to gateways: SwetsnetNavigator, Information Quest, EBSCO Online l Links to aggregators - Ingenta/CatchWord l Links to document delivery vendors eg Infotrieve l SFX (OpenURL) enabled l CrossRef

Our experience with CrossRef IOP is primary and secondary Primary = 36 electronic journals Secondary = Axiom dbase (INSPEC and Compendex) Enables links to many publishers where no other arrangement exists Sweeps up 7% refs in electronic journals >25% links from INSPEC (Axiom)

How much do we use CrossRef? IOP electronic journals 1968-present 2.8m references 1.8m have at least one link (64%) 1.2m INSPEC or Compendex (66%) 816k to 2’ry eg Chemport, SWETS (45%) 608k bilateral to publisher (34%) 225k to IOP article (13%) 37k to preprint, eg arXiv, SPIRES (2%) 37k to CrossRef (2%) - half Elsevier Total no of links 3m 1m references have no link (36%)

How much do we use CrossRef (2)? IOP electronic journals whole year k references 126k have at least one link (70%) 77k INSPEC or Compendex (62%) 80k to 2’ry eg Chemport, SWETS (63%) 49k bilateral to publisher (39%) 14k to IOP article (11%) 6k to preprint, eg arXiv, SPIRES (5%) 8k to CrossRef (7%) - half Elsevier Total no of links 248k 53k references have no link (30%)

How much do we use CrossRef (3)? Axiom INSPEC year k new journal records 55k CrossRef links (28%) 52k bilateral links (27%) 88k have no links (45%)

How much do we use CrossRef (4)? Axiom click-throughs pointing to full text (last 12 months) 104k total 55k AIP/APS (53%) 37k CrossRef (36%) 12k remainder (12%)

How much - summary In current IOP electronic journals, refs 70% have a link (or links) inc CrossRef 7% rely on CrossRef link 30% of refs have no link to full text In current Axiom (INSPEC) 55% have a link (or links) inc CrossRef 28% we rely on CrossRef link 45% of refs have no link to full text (back sweeps may reduce this)

What’s our experience of using CrossRef? We support the principle We love all the nice people Technically…it’s not been easy EJs - not much problem Axiom - more tricky

Axiom technical problems 5000 new abstracts per week About 30% need CrossRef links Much staff time dealing with it Manual reference check Data deviating from the spec Often“Timed Out” with no notice Now backlog of >300,000 look-ups Recently stopped using CrossRef at all! New CrossRef system seems better :-) Working for EJs; Axiom will try soon

Other issues with CrossRef Transfer of ownership Not seamless if new owner fails to update metadata (new URL for the DOI) Affiliates need not link to primary source! Primary publishers must do so Secondary need not. WHY NOT? 60%members deposit but don’t link! So we send them readers... but they don’t send readers to us! These are not the fault of CrossRef staff MEMBERS - COME ON, PLAY THE GAME !

How much does CrossRef cost us? For electronic journals p.a. Membership $1000 Deposit articles$6500 Retrieve articles$500 For Axiom p.a. Membership$5000 Retrieve articles$8500 For archive (one off) Deposit$8250 Retrieve$8500

How much does CrossRef cost us? Year 2001 invoices = $28,000

How should CrossRef develop? l EVERYTHING TO IMPROVE LINKING l More links to books and grey literature l Affordable subsets of MDDB we can buy l Good for CrossRef as well as for us l Linking tools - e.g. graphical “history” of a “reference trail” l Forward citation: deposit refs attached to papers. Let’s not repeat history! l Cross Search abstracts - NO NO! l Move away from core role - linking (PILA) l It’s competing with secondaries

Summary IOP always keen on reference linking Many linking relationships CrossRef (in physics) is valuable sweep up CrossRef (for Axiom) is largest single link We support CrossRef, value relationship Technical problems may be resolved? Future: more linking items, not searching grey literature MDDB slices reference trails forward citing!!!!

Thank you