When each line of code is written it is surrounded by a sea of context: who in the community this is for, what problem we’re trying to solve, what technical assumptions we’re making, what we already tried but didn’t work, how much coffee we’ve had today. All of these have an effect on the software we write.
By the time the next person looks at that code, some of that context will have evaporated.
It turns out that one of the things that is really difficult at Crossref is checking whether a set of Crossref credentials has permission to act on a specific DOI prefix. This is the result of many legacy systems storing various mappings in various different software components, from our Content System through to our CRM. To this end, I wrote a basic application, credcheck, that will allow you to test a Crossref credential against an API.
Subject classifications have been available via the REST API for many years but have not been complete or reliable from the start and will soon be deprecated.
The subject metadata element was born out of a Labs experiment intended to enrich the metadata returned via Crossref Metadata Search with All Subject Journal Classification codes from Scopus. This feature was developed when the REST API was still fairly new, and we now recognize that the initial implementation worked its way into the service prematurely.
Crossref and DOAJ share the aim to encourage the dissemination and use of scholarly research using online technologies and to work with and through regional and international networks, partners, and user communities for the achievement of their aims to build local institutional capacity and sustainability. Both organisations agreed to work together in 2021 in a variety of ways, but primarily to ‘encourage the dissemination and use of scholarly research using online technologies, and regional and international networks, partners and communities, helping to build local institutional capacity and sustainability around the world.
Members can participate in Cited-by by completing the following steps:
Deposit references for one or more prefixes as part of your content registration process. Use your Participation Report to see your progress with depositing references. This step is not mandatory, but highly recommended to ensure that your citation counts are complete.
We will match the metadata in the references to DOIs to establish Cited-by links in the database. As new content is registered, we automatically update the citations and, for those members with Cited-by alerts enabled, we notify you of the new links.
Display the links on your website. We recommend displaying citations you retrieve on DOI landing pages, for example:
If you are a member through a Sponsor, you may have access to Cited-by through your sponsor – please contact them for more details. OJS users can use the Cited-by plugin.
Citation matching
Members sometimes submit references without including a DOI tag for the cited work. When this happens, we look for a match based on the metadata provided. If we find one, the reference metadata is updated with the DOI and we add the "doi-asserted-by": "crossref" tag. If we don’t find a match immediately, we will try again at a later date.
There are some references for which we won’t find matches, for example where a DOI has been registered with an agency other than Crossref (such as DataCite) or if the reference refers to an object without a DOI, including conferences, manuals, blog posts, and some journals’ articles.
To perform matching, we first check if a DOI tag is included in the reference metadata. If so, we assume it is correct and link the corresponding work. If there isn’t a DOI tag, we perform a search using the metadata supplied and select candidate results by thresholding. The best match is found through a further validation process. Learn more about how we match references. The same process is used for the results shown on our Simple Text Query tool.
All citations to a work are returned in the corresponding Cited-by query.
Page owner: Isaac Farley | Last updated 2023-April-28