IFLA Library Reference Model

The IFLA Library Reference Model (IFLA LRM) is a conceptual entity–relationship model developed by the International Federation of Library Associations and Institutions (IFLA) that expresses the "logical structure of bibliographic information". It unifies the models of Functional Requirements for Bibliographic Records (FRBR), Functional Requirements for Authority Data (FRAD), and Functional Requirements for Subject Authority Data (FRSAD).

Source: Wikipedia — IFLA Library Reference Model (CC BY-SA 4.0)