I wonder whether there exists any well-established database schema(s) to store references.
For example, the Perl package Bib2ML (aka. Bib2HTML) contains a
bib2sql tool that generates a SQL database from a BibTeX database, with the following schema:
If there is no well-established schema, I am still interested to know about alternatives. One can assume the data it contains can be extracted from the paper or the BibTeX (i.e. no need to be able to store information coming from other sources, and the focus is on the reference, not the paper's content).