This list is a stub, please extend it !
Here is a beginning of list of places where Wikisource deals with metadata:
- WS microformat is a custom set of HTML clasees that is used by templates of a lot of Wikisources (including English Wikisource). Some tools already use it like Wsexport that use it in order to add metadata to exported books.
- en:Template:Author and fr:Modèle:Auteur implements the hcard microformat.
- Some pages of French Wikisource implement also the CoinS system.