This year, metadata development is one of our key priorities and we’re making a start with the release of version 5.4.0 of our input schema with some long-awaited changes. This is the first in what will be a series of metadata schema updates.
What is in this update?
Publication typing for citations
This is fairly simple; we’ve added a ‘type’ attribute to the citations members supply. This means you can identify a journal article citation as a journal article, but more importantly, you can identify a dataset, software, blog post, or other citation that may not have an identifier assigned to it. This makes it easier for the many thousands of metadata users to connect these citations to identifiers. We know many publishers, particularly journal publishers, do collect this information already and will consider making this change to deposit citation types with their records.
Every year we release metadata for the full corpus of records registered with us, which can be downloaded for free in a single compressed file. This is one way in which we fulfil our mission to make metadata freely and widely available. By including the metadata of over 165 million research outputs from over 20,000 members worldwide and making them available in a standard format, we streamline access to metadata about scholarly objects such as journal articles, books, conference papers, preprints, research grants, standards, datasets, reports, blogs, and more.
Today, we’re delighted to let you know that Crossref members can now use ROR IDs to identify funders in any place where you currently use Funder IDs in your metadata. Funder IDs remain available, but this change allows publishers, service providers, and funders to streamline workflows and introduce efficiencies by using a single open identifier for both researcher affiliations and funding organizations.
As you probably know, the Research Organization Registry (ROR) is a global, community-led, carefully curated registry of open persistent identifiers for research organisations, including funding organisations. It’s a joint initiative led by the California Digital Library, Datacite and Crossref launched in 2019 that fulfills the long-standing need for an open organisation identifier.
We began our Global Equitable Membership (GEM) Program to provide greater membership equitability and accessibility to organizations in the world’s least economically advantaged countries. Eligibility for the program is based on a member’s country; our list of countries is predominantly based on the International Development Association (IDA). Eligible members pay no membership or content registration fees. The list undergoes periodic reviews, as countries may be added or removed over time as economic situations change.
Cited-by supports members who display citations, enabling the community to discover connections between research outputs.
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 references deposited 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 relationship between the two works is created. Crossref logs these relationships and updates the citation counts for each work. You can retrieve citation counts through our public APIs.
Members can use the Cited-by service to retrieve the full list of citing works, along with all the bibliographic details needed to 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.
Depositing references is not a requirement, but strongly encouraged if you are using Cited-by.
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.
Depositing your own references is strongly encouraged if you use Cited-by. If you don’t, the citations you retrieve will not include those from your own works. This is likely to lead to under-reporting of citations counts by at least 20% and you are missing the opportunity to point readers to other similar works on your platform.
Also in the metadata is the number of citations a work has received, under the tag "is-referenced-by-count".
To retrieve the full list of citations you need be a member using Cited-by. While anyone can use an API query to see the number of citations a work has received, members can retrieve a full list of citing DOIs and callback notifications informing them when one of their works has been cited. Details of the citing works can be displayed on your website alongside the article.
In 2023 we are developing a new API endpoint that will make citations more accessible to the community, for a preview see this announcement.
