More than one billion citations now available in COCI!

«The competitive benefits of closing access to citation data diminish with each new citation released to the public domain, but the benefits of open data remain. Going forward, citation data is almost completely public domain».

With these words, from the article «A tipping point for open citations data» (July 15, 2021), Ian Hutchins celebrated the threshold crossing of one billion citations on public-domain databases in February 2021.

A crucial event that preceded this COCI release was Elsevier’s endorsement in the DORA Declaration on Research Assessment in December 2020, thereby making «reference lists for all articles published in Elsevier journals openly available via Crossref so they can be available for reuse. This means other important initiatives like I4OC can draw on this metadata». Elsevier’s welcome commitment led to the opening of many previously closed references from its numerous academic journals submitted to Crossref. Now, after an extended period of data ingestion and processing, all these newly opened Elsevier references are available at OpenCitations within COCI, the OpenCitations Index of Crossref open DOI-to-DOI citations.

Now, a new significant milestone has been reached. COCI has just been extended with more than 92 Million additional citations. Its most recent release, the COCI September 2021 release, now contains a total of 1.18 Billion DOI-to-DOI citation links derived from open references within Crossref.

This latest release includes citations from the most recent articles published by the American Chemical Society, whose bibliographic references were opened in February 2021. The ACS back number citations will be available in the next COCI release, when a new processing of all the Crossref data will be completed.


As a reminder, the journals of our publisher PC TECHNOLOGY CENTER are also available via Crossref:

Eastern-European Journal of Enterprise Technologies

Technology audit and production reserves

ScienceRise: Medical Science

ScienceRise: Pedagogical Education

ScienceRise: Pharmaceutical Science

ScienceRise: Biological Science

ScienceRise: Juridical Science


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