Keywords centrally registered identifier
cstr Common Science and Technology Resources
datacite DataCite Ontology
doi Digital Object Identifier
ec Enzyme Nomenclature
funderregistry FunderRegistry
grid Global Research Identifier Database
hdl Handle
igsn International Generic Sample Number
inchi InChI
orcid Open Researcher and Contributor
raid Research Activity Identifier
ror Research Organization Registry
rrid Research Resource Identification
viaf Virtual International Authority File