json [ { "oci": "02001010806360107050663080702026306630509-0200101080636102703040309", "citing": "10.1186/1756-8722-6-59", "cited": "10.1186/ar3439", "creation": "2013", "timespan": "P2Y", "journal_sc": "no", "author_sc": "no" }, { "oci": "02001010806360107050663080702026306630509-0200101080636102704000806", "citing": "10.1186/1756-8722-6-59", "cited": "10.1186/ar4086", "creation": "2013", "timespan": "P1Y", "journal_sc": "no", "author_sc": "no" }, { "oci": "02001010806360107050663080702026306630509-020010200003619122437020001023704023707090006", "citing": "10.1186/1756-8722-6-59", "cited": "10.1200/jco.2012.42.7906", "creation": "2013", "timespan": "P0Y", "journal_sc": "no", "author_sc": "no" }, { "oci": "02001010806360107050663080702026306630509-02003010009360008080300010805370200010237060604070907", "citing": "10.1186/1756-8722-6-59", "cited": "10.3109/08830185.2012.664797", "creation": "2013", "timespan": "P0Y", "journal_sc": "no", "author_sc": "no" }

COCI, the OpenCitations Index of Crossref open DOI-to-DOI citations, is an RDF dataset containing details of all the citations that are specified by the open references to DOI-identified works present in Crossref, as of the latest COCI update*

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Open Citation Identifiers

Each Open Citation Identifier [[OCI]] has a simple structure: the lower-case letters "oci" followed by a colon, followed by two numbers separated by a dash (e.g. https://w3id.org/oc/index/coci/ci/02001010806360107050663080702026306630509-02001010806360107050663080702026305630301), in which the first number identifies the citing work and the second number identifies the cited work.