Each OCI (Open Citation Identifier) has a simple structure: oci:<identifier>-<identifier>, where “oci:” is the identifier prefix, and is used to identify a citation as a first-class data entity - see https://doi.org/10.6084/m9.figshare.7127816.v2 for additional information. In each OCI, the first <identifier> is the identifier for the citing bibliographic resource, while the second <identifier> is the identifier for the cited bibliographic resource.