gml:userDefinedCS is an association role to the user defined coordinate system used by this CRS.
<gml:userDefinedCS xlink:href="" nilReason="" xmlns:gml="http://www.opengis.net/gml/3.2"> <gml:UserDefinedCS aggregationType="" gml:id="">{1,1}</gml:UserDefinedCS> </gml:userDefinedCS>
<element name="userDefinedCS" type="gml:UserDefinedCSPropertyType"> <annotation> <documentation>gml:userDefinedCS is an association role to the user defined coordinate system used by this CRS.</documentation> </annotation> </element>