<xs:attribute name="class">
    <xs:simpleType>
        <xs:restriction base="xs:token">
            <xs:enumeration value="copyeditor" />
            <xs:enumeration value="graphicdesigner" />
            <xs:enumeration value="other" />
            <xs:enumeration value="productioneditor" />
            <xs:enumeration value="technicaleditor" />
            <xs:enumeration value="translator" />
        </xs:restriction>
    </xs:simpleType>
</xs:attribute>