<xs:element name="areaspec">
    <xs:complexType>
        <xs:choice maxOccurs="unbounded">
            <xs:element ref="docbook:area" />
            <xs:element ref="docbook:areaset" />
        </xs:choice>
        <xs:attribute name="role" />
        <xs:attributeGroup ref="docbook:db.common.attributes" />
        <xs:attributeGroup ref="docbook:db.common.linking.attributes" />
        <xs:attribute name="units">
            <xs:simpleType>
                <xs:restriction base="xs:token">
                    <xs:enumeration value="calspair" />
                    <xs:enumeration value="linecolumn" />
                    <xs:enumeration value="linecolumnpair" />
                    <xs:enumeration value="linerange" />
                    <xs:enumeration value="other" />
                </xs:restriction>
            </xs:simpleType>
        </xs:attribute>
        <xs:attribute name="otherunits" type="xs:NMTOKEN" />
    </xs:complexType>
</xs:element>