IFLA Library Reference Model

RDA is an implementation of the IFLA Library Reference Model (LRM).

The LRM is a high-level conceptual reference model developed within an entity-relationship modelling framework by the International Federation of Library Associations and Institutions (IFLA).

The functional scope of the model is taken from a set of tasks that are defined from the point of view and needs of the end-user of library and cultural heritage resources:

  • Find: To bring together information about one or more resources of interest by searching on any relevant criteria.
  • Identify: To clearly understand the nature of the resources found and to distinguish between similar resources.
  • Select: To determine the suitability of the resources found, and to be enabled to either accept or reject specific resources.
  • Obtain: To access the content of the resource.
  • Explore: To discover resources using the relationships between them and thus place the resources in a context.

LRM entities

The entities defined in the LRM are "the key objects of interest to users of library information systems":

The classes representing these entities are disjoint.

The Agent entity is divided into two sub-entities:

The classes representing these sub-entities are disjoint.

The Agent entity is strictly equivalent to the union of the two sub-entities. That is, an agent is one or more persons.

The LRM uses a super-entity to support class inheritance:

The class representing this entity is a super-class of all other LRM classes.

LRM namespace

The LRM namespace is