Open Access linking and configuration options

Third Iron is committed to providing the best discoverability of and access to Open Access articles. This article describes how Third Iron accomplishes this.

Open Access awareness

LibKey is a core technology used across all Third Iron products. LibKey is an informed linking solution, one that understands what content is available to a user, both from Open Access and library subscribed sources, and how to create the fastest, most reliable link to it.

LibKey Open Access linking has been enhanced with Unpaywall data which adds article-level open access knowledge to Third Iron’s already substantial understanding of title-level Open Access journals. Additionally, Third Iron has taken the unique step of locally loading and synthesizing this data into our resolution waterfall, providing libraries four important advantages.

First, this enables us to ensure that LibKey is only linking to the version of record (VoR), then giving libraries the option of enabling linking to non-VoR articles, such as accepted, peer-reviewed manuscripts. This is a marked step forward from standard uses of Unpaywall data which typically present links to an article, irrespective of version. This can result in users being linked unknowingly to a non-VoR article which may have been altered substantially after undergoing editorial and peer-review.

Second, locally loading the data affords the opportunity to add data that might be missing from the Unpaywall links. For example, some Unpaywall records only include links to the HTML version of an article where a PDF link is otherwise available. Third Iron is frequently able to add the PDF link.

Third, Unpaywall data provides identifier based linking that does not require authentication. This means that if an article is available, the link reliability will increase and the time to access it will decrease, furthering LibKey’s goal of providing fast and reliable full text linking.

Fourth, hosting the data means that the Third Iron Support team can adjust links if errors are found or reported, rather than simply passing on the report to Impact Story. This provides a much faster response time.

Library Holdings an Open Access Article Linking

The linking waterfall in BrowZine/LibKey is part of the AI Expert system that determines the best link available.  It can be articulated clearly through the following diagram:

First, the article is checked to see if there is a Version of Record (VoR) Open Access link to this article available.  If there is, that linking destination is chosen regardless of the holdings data supplied about this article from the library.  The contents of this data set come from a unique combination of Third Iron curated knowledgebases, Unpaywall data and other sources.

Importantly then for libraries: there is not a need to flesh out your link resolver knowledgebase with "open access packages" such as those from the DOAJ to enable these titles for linking.  A common issue we see with some of these packages is that they may include "partially" open access titles where a number of individual articles are available but many are still only visible to subscribers.  Adding these to your "holdings" can create havoc for researchers because some articles will work and some will not.  To make these articles available in LibKey, it is recommended to NOT activate these packages and instead allow LibKey to identify these articles during the linking process.

However, there may be other good reasons to add these to your knowledge base, as it may be used to create the searchable set of records within your discovery system for example.  Additionally, BrowZine will ONLY display titles that you have added to your collection for browsing.  This is because we view BrowZine as a "curated" set of content appropriate for a particular library.  For example, a medical library may not appreciate lots of open access engineering materials within their BrowZine library.

After open access article linking options are exhausted, LibKey checks the holdings for the library with a priority placed on any publisher sources due to the enhance reliability of linking to publisher sources as well as inclusion of Article in Press content, where available.

If no subscribed sources are available, LibKey will attempt to find a non-version of record open access article that has been accepted for publication ("Accepted Manuscript") via Unpaywall.  This feature is available in most, but not all products (see below in "Configuration Options").

And finally, within certain contexts (BrowZine, LibKey Nomad, Link, .io) linking options to your link resolver, ILL or document delivery may be provided for a complete fulfillment solution.

About Published Version, Accepted Manuscripts and Submitted Manuscripts

These versions of Open Access material are derived from the DRIVER-Version Mapping scheme which takes a number of different "statuses" of articles in their life cycle and effectively breaks them into three groupings that can be interpreted like this:

Published Version: Is the Version of Record (VoR)
Accepted Version: Is peer-reviewed, but lacks publisher specific formatting
Submitted Version: Is *not* peer-reviewed

As such, LibKey ALWAYS includes the Published Version of Record in its Open Access linking calculations, it by default optionally includes the Accepted Version in a number of contexts outlined below in the Configuration Options section and it *never* includes the Submitted version of Open Access materials.

This is because LibKey is licensed and integrated into libraries who typically prefer their users to see the version of record or at least the accepted version of a paper that has undergone peer review but to not link users to a version of the paper which may have undergone significant changes from the point of submission to the point where it has been edited and updated post peer-review.  Instead, these version are skipped over in favor of providing a route for ILL/Document delivery fulfillment to the version of record.

Configuration Options

The BrowZine products utilize only the publishers version of record version of articles when linking to open access content.  No options exist to extend this capability.

By contrast, LibKey technologies from Third Iron also have enabled by default the ability to view Accepted Manuscripts powered by Unpaywall data within the product.  These include:
  • LibKey Nomad
  • LibKey Link
However, it may be desirable to NOT utilize non Version of Record articles and instead have LibKey refer users to an ILL/Document Delivery system if no holdings are found.  Linking to these non-version of record articles can be disabled by contacting Third Iron support ( which will force the above LibKey technologies to ONLY link to OA content when the link provided is the version of record.

Additionally, the following LibKey Discovery integrations also offer this ability and are enabled by default:
  • LibKey Discovery: Primo
  • LibKey Discovery: Summon
To disable the display of Accepted Manuscripts in one of these integrations, a library can simply edit the configuration scripts around these options as detailed in the Primo or Summon LibKey Discovery integration. documentation.  If you need further guidance, don't hesitate to contact us at

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