<xs:complexType name="BoundaryType">
    <xs:sequence>
      <xs:element name="class" minOccurs="0" type="gml:CodeType"/>
      <xs:element name="function" maxOccurs="unbounded" minOccurs="0" type="gml:CodeType"/>
      <xs:element name="usage" maxOccurs="unbounded" minOccurs="0" type="gml:CodeType"/>
      <xs:element name="offset" minOccurs="0" type="gml:LengthType"/>
      <xs:element name="offsetDirection" minOccurs="0" type="xs:string"/>
      <xs:element name="location" minOccurs="0" type="gml:MultiCurvePropertyType"/>
    </xs:sequence>
  </xs:complexType>