About the RDA Registry and vocabularies

Representing the RDA ontology

4-fold path

The RDA Development Team is developing extensions to the RDA element sets to accommodate data from the "4-fold path".

There are three methods for using a string to identify a related entity:

  • An unstructured description: a plain literal, for example a free text note or a transcription.
  • A structured description: a literal typed with a form of syntax encoding scheme that aggregates literal values from other elements, for example a name/title access point.
  • An identifier: a literal that may be typed with a form of syntax encoding scheme that aggregates literal values from other elements, for example an ISBN or local identifier.

The fourth method uses a URI to identify the related entity as a linked data thing.