Citation.js converts formats like BibTeX, Wikidata JSON and ContentMine JSON to CSL-JSON to convert to other formats like APA, Vancouver and back to BibTeX.
AFAIK, it's only a problem for certain DataCite DOIs, when submitted (or any other date) is nil. In that case, Bolognese, the DataCite metadata conversion utility (mistakenly, I assume) returns date_parts instead of date-parts. I made a PR: https://github.com/datacite/bolognese/pull/27.
Caused due to this line:
https://github.com/larsgw/citation.js/blob/97641fa1cfc753c261adcc25efe0aa9284418536/src/parse/modules/doi/json.js#L24
AFAIK, it's only a problem for certain DataCite DOIs, when
submitted(or any other date) isnil. In that case, Bolognese, the DataCite metadata conversion utility (mistakenly, I assume) returnsdate_partsinstead ofdate-parts. I made a PR: https://github.com/datacite/bolognese/pull/27.