1. CrossRef Case Study Elsevier & Local Hosting Chris Shillum Karen Hunter

2. Elsevier, CrossRef & IDF largest depositor of metadata & DOIs thus far (about 1 million articles) member of the IDF and CrossRef boards start-up lender to both IDF and CrossRef have clear policy that want links via CR bottom line: heavily invested and dedicated to making CrossRef and DOI work

3. Elsevier and Uses of DOI ScienceDirect primary journals -- SD & SDOS secondary (a & i) services –on ScienceDirect –elsewhere on the Web (Embase.com) BioMedNet, ChemWeb, EiVillage Endeavor MDL

4. Local Hosting Elsevier receives a copy of the full CrossRef metadata database at ScienceDirect in Dayton (Lexis-Nexis) use of the database is restricted to extraction of the DOI for ES products we pay for all non-ES records delivered, whether used or not matching is done on-the-fly

5. Primary Journals on SD depositing all ES articles on SD (now 1995+, but backfile project underway) not yet deposited third party publishers therefore, only linking from references in ES titles reminder: you can only link out from references in articles that have themselves been deposited with CrossRef

6. Secondary Services on ScienceDirect -- a combination of services owned by Elsevier (Compendex, Embase, Beilstein, Geobase, Biobase, etc.) and those licensed in (Biosis, Inspec, EconLit, etc.) links are made to all records found in the CrossRef metadata database

7. Other Services links not yet in place for non-ScienceDirect remote services (e.g., SDOS inward and outward links, BioMedNet, Endeavor, etc.) developments under way for DOI retrieval for all services

8. Why Local Host? Better fit with existing linking infrastructure Maintain dynamic, pre-resolved linking –CrossRef 1.0 designed for (semi-)static, pre-resolved links Avoid building DOI lookup caching infrastructure No quality of service dependency Single CrossRef interface for multiple product platforms

9. ScienceDirect/CrossRef Implementation path DOI assignment scheme –Based on existing PII identifiers, assigned to all our articles back to 1995 CrossRef batch submission –Based on existing “Article Catalogue” –Convert to CrossRef DTD and add DOIs Local-hoster batch receipt –Based on existing gateway architecture –Covert CrossRef batches and load to linking table Response page –Modify to add bibliographic info and CrossRef info

10. ScienceDirect Content Database Content Fabrication Web Interface Content Gateway Infrastructure Article Catalogue Links Database CrossRef Components CrossRef Batch Loader CrossRef Batch Submission CrossRef Gateway Partner ScienceDirect/CrossRef Architecture

11. Lessons learned along the way Inventory management difficult –Both inbound and outbound Pain to parse local loader batch logs Testing (of outbound links) a difficult, manual process

12. Still to do “Outward linking hub” –Provide access to links database for other Elsevier platforms –Provide access to links database to local systems customers Multi-publisher CrossRef feed –Agent service for hosted content

13. http://www.sciencedirect.com