Each OCI (Open Citation Identifier) has a simple structure: oci:number-number, where “oci:” is the identifier prefix, and is used to identify a citation as a first-class data entitiy - see https://opencitations.wordpress.com/2018/02/19/citations-as-first-class-data-entities-introduction/ for additional information. OCIs for citations stored within the OpenCitations Corpus are constructed by combining the OpenCitations Corpus local identifiers for the citing and cited bibliographic resources, separating them with a dash. For example, oci:2544384-7295288 is a valid OCI for the citation between two papers stored within the OpenCitations Corpus. OCIs can also be created for bibliographic resources described in an external bibliographic database, if they are similarly identified there by identifiers having a unique numerical part. For example, the OCI for the citation that exists between Wikidata resources Q27931310 and Q22252312 is oci:01027931310–01022252312. OCIs can also be created for bibliographic resources described in external bibliographic database such as Crossref or DataCite where they are identified by alphanumeric Digital Object Identifiers (DOIs), rather than purely numerical strings.

Prefix
oci
Links
Homepage
Contact
Missing Contact
Pattern
^[0-9]+-[0-9]+$
Namespace in Pattern
False
Example Identifier
1-18   Resolve
Metaregistry

The metaregistry provides mappings between the Bioregistry and other registries. There are 3 mappings to external registries for oci.

Registry Name Metaprefix Metaidentifier
Identifiers.org miriam oci
Name-to-Thing n2t oci
Prefix Commons prefixcommons OCI
Providers

Providers are various services that resolve CURIEs to URLs. The example CURIE oci:1-18 is used to demonstrate the provides available for oci. Generation of OLS and BioPortal URLs requires additional programmatic logic beyond string formatting.

Name Metaprefix URL
Open Citation Identifier oci https://w3id.org/oc/oci/1-18
Bioregistry bioregistry https://bioregistry.io/oci:1-18
Identifiers.org miriam https://identifiers.org/oci:1-18
Name-to-Thing n2t https://n2t.net/oci:1-18