The state of inventaire.io experiments on a federated database on books using Wikidata entities, properties, and data model Maxime Lathuilière at WikiCite 2017.
Has an entities map .... works, editions....don't yet trust Wikidata on editions bc too chaotic (ISBNs set on works, etc), Inventaire must accept all books (even by authors that are not well known, Wikidata cant do this), so Inventaire also has an internal db