gml:imageDatum is an association role to the image datum used by this CRS.
<gml:imageDatum xlink:actuate="" xlink:arcrole="" xlink:href="" nilReason="" gml:remoteSchema="" xlink:role="" xlink:show="" xlink:title="" xlink:type="simple"> <gml:ImageDatum gml:id="">{1,1}</gml:ImageDatum> </gml:imageDatum>
<element name="imageDatum" type="gml:ImageDatumPropertyType"> <annotation> <documentation>gml:imageDatum is an association role to the image datum used by this CRS.</documentation> </annotation> </element>