Each publication should have structured bibliographic metadata associated with it. This should be expressed as a separate file stored adjacent to or within the publication package. When possible, this should be expressed in a standard format such as e.g. ONIX, JATS, or Dublin Core. In order to process metadata at scale, the file naming convention, location of the file relative to the publication, and format should all remain consistent.
These guidelines may add context when deciding how to format bibliographic metadata and where to store it:
3. Use existing standards when creating metadata
22. Express metadata in an appropriate structured format
30. Add bibliographic metadata to an EPUB
45. Embed bibliographic metadata in a web page