This blog post is from Lettie Conrad and Michelle Urberg, cross-posted from the The Scholarly Kitchen.
As sponsors of this project, we at Crossref are excited to see this work shared out.
The scholarly publishing community talks a LOT about metadata and the need for high-quality, interoperable, and machine-readable descriptors of the content we disseminate. However, as we’ve reflected on previously in the Kitchen, despite well-established information standards (e.g., persistent identifiers), our industry lacks a shared framework to measure the value and impact of the metadata we produce.
When Crossref began over 20 years ago, our members were primarily from the United States and Western Europe, but for several years our membership has been more global and diverse, growing to almost 18,000 organizations around the world, representing 148 countries.
As we continue to grow, finding ways to help organizations participate in Crossref is an important part of our mission and approach. Our goal of creating the Research Nexus—a rich and reusable open network of relationships connecting research organizations, people, things, and actions; a scholarly record that the global community can build on forever, for the benefit of society—can only be achieved by ensuring that participation in Crossref is accessible to all.
In August 2022, the United States Office of Science and Technology Policy (OSTP) issued a memo (PDF) on ensuring free, immediate, and equitable access to federally funded research (a.k.a. the “Nelson memo”). Crossref is particularly interested in and relevant for the areas of this guidance that cover metadata and persistent identifiers—and the infrastructure and services that make them useful.
Funding bodies worldwide are increasingly involved in research infrastructure for dissemination and discovery.
Preprints have become an important tool for rapidly communicating and iterating on research outputs. There is now a range of preprint servers, some subject-specific, some based on a particular geographical area, and others linked to publishers or individual journals in addition to generalist platforms. In 2016 the Crossref schema started to support preprints and since then the number of metadata records has grown to around 16,000 new preprint DOIs per month.
Cited-by gives our members full access to citations, helping them to build a picture of how research has been received by the community.
Scholars use citations to critique and build on existing research, acknowledging the contributions of others. Members can include references in their metadata deposits which Crossref uses to create links between works that cite each other. The number of citations each work receives is visible to anyone through our public APIs. Through our Cited-by service, members who deposit reference metadata can retrieve everything they need to display citations on their website.
Members who use this service are helping readers to:
easily navigate to related research,
see how the work has been received by the wider community,
explore how ideas evolve over time by highlighting connections between works.
Watch the introductory Cited-by animation in your language:
Cited-by begins with depositing references as part of the metadata records for your content. Learn more about depositing references.
A member registers content for a work, the citing paper. This metadata deposit includes the reference list. Crossref automatically checks these references for matches to other registered content. If this is successful, a citation is created.
Crossref logs the citations and updates the citation counts for each work. You can retrieve citation counts through our public APIs. Members who deposit references can sign up for the Cited-by service to retrieve the full list of citing works (not just the count), and can display them on their website.
Note that citations from Crossref may differ from those provided by other services because we only look for links between Crossref-registered works and don’t share the same method to find matches.
Obligations and fees for Cited-by
Participation in Cited-by is optional, but encouraged
There is no charge for Cited-by
You must include references when you register content in order to be eligible for Cited-by
You only retrieve Cited-by metadata for your own content.
Best practice for Cited-by
Because citations can happen at any time, Cited-by links must be kept up-to-date. Members should either check regularly for new citations or (if performing XML queries) set the alert attribute to true. This means the search will be saved in the system and you’ll get an alert when there is a new match.
Also in the metadata is the number of citations a work has received, under the tag "is-referenced-by-count".
However, to retrieve the full list of citations for your own works, you need to use Cited-by. While anyone can use an API query to see the number of citations a work has received, through Cited-by the member who deposited the work can retrieve a list of citing DOIs. Details of the citing works can be displayed on your website alongside the article.
In addition, Cited-by users can receive callback notifications or emails informing them when one of their works has been cited.
