Multilingual Entity File (MEF)

A service that combines controlled names in multiple languages for the same entity (person, place, period...). Available as an API, it integrates with library management systems and thus allows collaborative management of authority data by institutions from different linguistic regions.


What does MEF do?

MEF is a service that combines entities (or authorities) in multiple languages. It then makes the data available to other systems, such as library management systems, as an API. MEF can therefore be used by several different interfaces, but does not have its own user interface.

MEF is operated by RERO ILS where it allows for example:

  • The user to search and display the contents (and not only the interface) in his/her own language
  • Libraries to reuse international repositories (GND, IdRef...) as much as possible. They can thus abandon the local management of an authority file and embrace the web of data

For example, RERO ILS uses MEF.

RERO+ is developing this service in an open way and makes it available, for the moment in a test version, at

Types of entities

MEF will eventually host the resource types defined in RDA standards and the Library Reference Model:

  • persons
  • families
  • corporate bodies
  • works
  • common nouns
  • places
  • time-spans
  • expressions

How it works

MEF retrieves and synchronizes with entities from different sources (GND, IdRef, etc.). It automatically aggregates them through VIAF, deriving display labels in German and French (at the moment) when available.

The entities themselves are maintained and edited directly at the source in agreement with their issuing institution. No entities are created or edited through MEF.