referenceSystems.xsd

See ISO/DIS 19136 13.2.
The reference systems schema components have two logical parts, which define elements and types for XML encoding of the definitions of:
-	Identified Object, inherited by the ten types of GML objects used for coordinate reference systems and coordinate operations
-	High-level part of the definitions of coordinate reference systems
This schema encodes the Identified Object and Reference System packages of the UML Model for ISO 19111.