<xs:attribute name="measurementUnits" default="feet">
    <xs:annotation>
        <xs:documentation>
				Measurement units
			</xs:documentation>
        <xs:appinfo>
				feet
			</xs:appinfo>
    </xs:annotation>
    <xs:simpleType>
        <xs:restriction base="xs:token">
            <xs:enumeration value="feet" />
            <xs:enumeration value="yard" />
            <xs:enumeration value="rod" />
            <xs:enumeration value="chain" />
            <xs:enumeration value="centimeter" />
            <xs:enumeration value="meter" />
            <xs:enumeration value="unknown" />
        </xs:restriction>
    </xs:simpleType>
</xs:attribute>