The Crossref Curriculum

Crossref XSD schema quick reference

Crossref supports additional schema (not listed here) for legacy purposes.

Deposit schema

Used for depositing (and updating) metadata and DOIs

Schema Purpose Status Further info
crossref4.4.2.xsd full metadata deposits recommended documentation
crossref4.4.1.xsd full metadata deposits available documentation
crossref4.4.0.xsd full metadata deposits available documentation
crossref4.3.7.xsd full metadata deposits available documentation
common4.3.7.xsd contains common elements used by other schema imported
crossref4.3.6.xsd full metadata deposits available documentation
fundref.xsd funding data imported
AccessIndicators.xsd license data imported
relations.xsd relationships between DOIs and other identifiers imported
clinicaltrials.xsd relationships between publications that report on a clinical trial imported
doi_resources4.4.2.xsd used to append or update specific sets of metadata to an existing record recommended documentation
doi_resources4.3.6.xsd used to append or update specific sets of metadata to an existing record available documentation
common4.4.2.xsd contains common elements used by other schema available documentation

Query schema

Schema Purpose Further info
Crossref_query_input2.0.xsd used to input XML queries to the system documentation

Metadata retrieval schema

Used for retrieving Crossref metadata

Schema Purpose Further info
crossref_query_output2.0.xsd returns query results in xsd_xml format, used for Cited-by results documentation
crossref_query_output3.0.xsd returns query results in UNIXSD format documentation
unixref1.1.xsd returns query results in the UNIXML format, also used to support the data delivered by our OAI-PMH service documentation
unixref1.0.xsd returns query results in the UNIXML format for some older content, also used to support the data delivered by our OAI-PMH service documentation
crossref_output3.0.1.xsd used to support data files generated for bulk data distribution documentation
OAI-PMH.cr.xsd accommodates differences between Crossref’s OAI-PMH implementation and the published Open Archives OAI 2.0 schema documentation

Last Updated: 2020 April 8 by Laura J. Wilkinson