1. Hiberlink is funded by the Andrew W. Mellon Foundation The Missing Link Proposal http://hiberlink.org #hiberlink http://mementoweb.org #memento Herbert Van de Sompel Los Alamos National Laboratory @hvdsomp

2. Herbert Van de Sompel Data Citation Workshop, April 17 2014 This Presentation Referencing scholarly resources on the Web; machine-use Assumption: Referenced resources behave like regular web resources, i.e. dynamic, ephemeral Take away: Need to augment the URI of the referenced resource to reference it Based on insights from: Memento - Time Travel for the Web Hiberlink - Addressing Reference Rot in Research Communication Open Annotation – Annotating (scholarly) resources

3. Herbert Van de Sompel Data Citation Workshop, April 17 2014 Reference Augmented with Time URI-R is referenced resource URI-R evolves over time (changes, disappears) Reference URI-R as it was accessed at a given moment in time, cf. “accessed on Feb 8 th 2012” style references Referencing info: URI-R ; datetime <a href=“URI-R” memento-date=“20130208”>link text In combination with Memento infrastructure, this allows accessing the version of URI-R as it was on 2013-02-08, if such version exists http://mementoweb.org/missing-link/

4. Herbert Van de Sompel Data Citation Workshop, April 17 2014 Reference Augmented with URI of Snapshot/Archived Resource URI-R is referenced resource URI-R evolves over time (changes, disappears) URI-M is a snapshot of the resource at the time of referencing Referencing info: URI-R ; URI-M <a href=“URI-R” memento-uri=“URI-M”>link text Why not URI-M? URI-R is the web currency for the referenced resource URI-R is understood by all web archives, not just the URI-M one URI-M is subject to link rot: web archives are not forever either http://mementoweb.org/missing-link/

5. Herbert Van de Sompel Data Citation Workshop, April 17 2014 Reference Augmented with URI of Segment Information? URI-R is referenced resource What needs referencing is a non-trivial segment (spatial, temporal) of URI-R. Let URI-A be a description of the segment Referencing info: URI-R ; URI-A <a href=“URI-R” segment-uri=“URI-A”>link text What is the nature of URI-A? A description of the segment An open annotation of URI-R that describes the segment Annotation expressed in terms of the real referenced resource, not the human/machine splash page

6. Herbert Van de Sompel Data Citation Workshop, April 17 2014 URI-A

7. Herbert Van de Sompel Data Citation Workshop, April 17 2014 URI-A

8. Herbert Van de Sompel Data Citation Workshop, April 17 2014 Dataset Use Case: Segments of Interest URI-A

9. Herbert Van de Sompel Data Citation Workshop, April 17 2014 Generic Proposal with Harvard Internet Persistence Project Provide a set of links that pertain to URI-R to address a variety of use cases: Link to archived/snapshot resource – web archiving case Link to cached resource – robustness case Link to author of resource – citation graph case Need as information for each link in link set: URI of linked resource Relation type, e.g. memento, duplicate, author (IANA rel types) Typically also date

10. Herbert Van de Sompel Data Citation Workshop, April 17 2014 Generic Proposal with Harvard Internet Persistence Project Link to archived/snapshot resource – web archiving case <a href=“URI-R” lset=“URI-M memento 20130208”>link text Link to cached resource – robustness case <a href=“URI-R” lset=“URI-C duplicate 20140412”>link text

11. Herbert Van de Sompel Data Citation Workshop, April 17 2014 Generic Proposal with Harvard Internet Persistence Project Link to author of resource – citation graph case <a href=“URI-R” lset=“URI-ORCID author>link text Link to annotation that describes segment <a href=“URI-R” lset=“URI-A segment>link text