IVOA Recommendation: StandardsRegExt: a VOResource Schema Extension for   Describing IVOA Standards
  This document describes an XML encoding standard for metadata about IVOA standards themselves, referred to as StandardsRegExt. It is intended to allow for the discovery of a standard via an IVOA identifier that refers to the standard. It also allows one to define concepts that are defined by the standard which can themselves be referred to via an IVOA identifier (augmented with a URL fragment identifier). Finally, it can also provide a machine interpretable description of a standard service interface. We describe the general model for the schema and explain its intended use by interoperable registries for discovering resources. 
Paul Harrison (Editor), Douglas Burke, Ray Plante, Guy Rixon, Dave   Morris (and the IVOA Registry Working Group)
astro-ph.IM