(22 May 2019) There has been a growing interest from libraries and other cultural heritage organizations in Wikidata. Of the many potential uses for Wikidata, one emerging area of focus has been using Wikidata as a hub for institutional identifiers. Many organizations maintain unique identifiers for people, subjects, works, etc. If these IDs are all added to Wikidata then you could seamlessly access data from dozens of sources if you know the Wikidata ID.
Find out more on how Wikidata could be integrated into Library data, see here.