Creates a value reference (OGC Filter version 2.0) or a property name (OGC Filter version 1.0)
that represents a value that is to be evaluated by a filter predicate.
At runtime, a predicate is evaluated by replacing the value reference (property name) by the value it refers to.
Creates a value reference (OGC Filter version 2.0) or a property name (OGC Filter version 1.0) that represents a value that is to be evaluated by a filter predicate.
At runtime, a predicate is evaluated by replacing the value reference (property name) by the value it refers to.