gml:SingleOperationPropertyType is a property type for association roles to a single operation, either referencing or containing the definition of that single operation.
<complexType name="SingleOperationPropertyType"><annotation><documentation>gml:SingleOperationPropertyType is a property type for association roles to a single operation, either referencing or containing the definition of that single operation.</documentation></annotation><sequence minOccurs="0"><element ref="gml:AbstractSingleOperation"/></sequence><attributeGroup ref="gml:AssociationAttributeGroup"/></complexType>