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A reference system is characterized in terms of its domain of validity: the spatial and temporal extent over which it is applicable. The basic GML element for temporal reference systems is gml:TimeReferenceSystem.  Its content model extends gml:DefinitionType with one additional property, gml:domainOfValidity.

Element information



gml:id [1..1]xsd:IDThe attribute gml:id supports provision of a handle for the XML element representing a GML Object. Its use is mandatory for all GML objects. It is of XML type ID, so is constrained to be unique in the XML document within which it occurs.from type gml:DefinitionBaseType

Used in

Substitution hierarchy

Sample instance

<gml:TimeReferenceSystem gml:id="ID">
      <gml:GenericMetaData>Any text, intermingled with:
         <!--any element-->
   <gml:identifier codeSpace="">string</gml:identifier>