CrossRef Lab's Reverse Lookup allows you to resolve a URL to the DOI that points to it. It can also report whether or not a host name and it's root domain belong to CrossRef members.
Here's a quick example. Say there was a DOI that resolves to
http://www.publisher.com/my_content.html
and you feed that URL to this service. This service would respond with
JSON containing a DOI that points to the URL and a flag indicating
that the root domain,
publisher.com
belongs to a CrossRef member:
{
"for": "http://www.publisher.com/my_content.html",
"doi": "10.5555/my_content",
"root": {
"hostname": "publisher.com",
"crossref_member": true
}
}
There's an easy to use bookmarklet that can be used to determine if a web page and it's root domain belong to a CrossRef member. To use it, add this link to your bookmarks bar:
A hashed list of member root domains and subdomains is available for download here . All subdomains and root domains that appear in the resolution URL of any CrossRef DOI are included in the list.
To use the list hash your query subdomain or root domain with SHA2 256-bit, take the digest as a hex string and search for a match.
To get the DOI and member status associated with a URL and root domain, POST the
full URL, or just a hostname to
http://reverse.crrd.dyndns.org
much like in this curl example:
$ curl --data-binary "http://www.publisher.com/content52.html" http://reverse.crrd.dyndns.org
{
"for": ""http://www.publisher.com/content52.html",
"doi": "10.5555/52",
"root": {
"hostname": "publisher.com",
"crossref_member": true
}
}
If there is a DOI associated with the exact URL - one that resolves to the URL -
a
doi
field will be returned. A missing
doi
field indicates that there is no DOI that resolves to the exact URL provided.
A
root
field will be returned containing a root domain and its CrossRef member
status. A root domain is considered as belonging to a CrossRef member if it
or any of its subdomains make up part of the resolution URL of any
CrossRef DOI.
Reverse DOI lookup is problematic since many publishers redirect from the resolution URL of a DOI to some other web content. Therefore it's unlikely that the URL eventually seen after following a DOI will be findable with this service.
Many publishers point their DOIs to a specific link-resolving subdomain of their root domain. This service will report the membership status of root domains, never specific subdomains, so that shouldn't be a problem. However, some publishers point their DOIs to a root domain which in turn then directs to other root domains. In this case, some of the publisher's root domains that do not have DOIs pointing to them would be reported incorrectly as not being CrossRef member domains.
The downloadable host data is based on CrossRef metadata that is not current. Newer publishers or publishers that have recently changed their root domain may be missing from the data.