All Crossref Services are offered in 0.20 US $ per article for article metadata in an xml formated.
1) DOIs making
JATS TECH give service for DOIs making in an XML file formatted according to the Crossref deposit schema.
2) Citation linking
In addition to using DOIs to link to references that appear in their content, Crossref members can retrieve the DOIs of other publications that cite their content. This optional service, called cited-by linking (previously forward linking), enables Crossref members to display cited-by links in the primary content that they publish.
JATS TECH give service for citation linking.
3) Funding Data
The funding data service collects funding source information for publications deposited with Crossref.
JATS TECH give service for funding data metadata.
4) Text & Data Mining
The CrossRef Text and Data Mining service addresses the issue of text and data mining scholarly literature by providing a CrossRef Metadata API that can be used by researchers to access the full text of content identified by CrossRef DOIs across publisher sites and regardless of their business model.
JATS TECH give TDM metadata services.
5) Deposing References
JATS TECH give service for depositing References or article metadata in an XML file formatted according to the Crossref deposit schema.