<group name="geometricPositionGroup">
  <annotation>
    <documentation>GML supports two different ways to specify a geometric position: either by a direct position (a data type) or a point (a geometric object). pos elements are positions that are "owned" by the geometric primitive encapsulating this geometric position. pointProperty elements contain a point that may be referenced from other geometry elements or reference another point defined elsewhere (reuse of existing points).</documentation>
  </annotation>
  <choice>
    <element ref="gml:pos"/>
    <element ref="gml:pointProperty"/>
  </choice>
</group>