ifc:IfcSurfaceFeatureTypeEnum

<xs:simpleType name="IfcSurfaceFeatureTypeEnum">
  <xs:restriction base="xs:string">
    <xs:enumeration value="mark"/>
    <xs:enumeration value="tag"/>
    <xs:enumeration value="treatment"/>
    <xs:enumeration value="userdefined"/>
    <xs:enumeration value="notdefined"/>
  </xs:restriction>
</xs:simpleType>