2 http://schemas.opengis.net/gml/3.1.1/profiles/gmlsfProfile/1.0.0/gmlsf2.xsd GML application schema used to assess compliance with the WFS 1.1 specification. This schema conforms to level SF-2 of the Simple Features Profile (OGC 06-049): there are no restrictions on the use of non-spatial properties. Feature having feature reference property in order to evaluate XLink processing behaviour.