Add bf:OclcNumber as identifier subclass

[jodiw01]

To facilitate future data exchange activities with OCLC, add bf:OclcNumber as an subclass of bf:Identifier. This change could also streamline the output of OCLC numbers in RDF, from this:

bf:identifiedBy bf:Local rdf:valueon1303623709</rdf:value> bf:assigner <bf:Agent rdf:about="http://id.loc.gov/vocabulary/organizations/ocolc"/> </bf:assigner> </bf:Local> </bf:identifiedBy>

to this:

bf:identifiedBy bf:OclcNumber rdf:valueon1303623709</rdf:value> </bf:OclcNumber> </bf:identifiedBy>

[klngwll]

A suggestion would be to add ID or Number to the Class (OclcID if broadly applicable, or OclcNumber if specific) and possibly specify relationship with https://id.loc.gov/vocabulary/identifiers/worldcat

[azaroth42]

Indication that the ontology is broken when you need to multiply your classes by the number of adopting institutions.

[jodiw01]

included in v2.4