This is a side question for the xbiblio developers: Is there an
accessible database schema for bibliographic metadata that supports
the sort of field granularity that xbiblio supports? Obviously systems
like Papers, Mendeley, etc. have databases where they stash all the
data that ultimately get xbiblio-ified. I’m wondering if there is a
"standard" (or more likely of course, several standards for those
data, either as some sort of formal schema or even a detailed
description.
In the case of Papers, the database layer is quite different from the CSL specs, and we have a translation layer to generate proper output based on the CSL specs.