<xs:element name="group">
    <xs:complexType>
        <xs:choice maxOccurs="unbounded">
            <xs:element ref="docbook:arg" />
            <xs:element ref="docbook:group" />
            <xs:element ref="docbook:option" />
            <xs:element ref="docbook:synopfragmentref" />
            <xs:element ref="docbook:replaceable" />
            <xs:element ref="docbook:sbr" />
        </xs:choice>
        <xs:attribute name="role" />
        <xs:attributeGroup ref="docbook:db.common.attributes" />
        <xs:attributeGroup ref="docbook:db.common.linking.attributes" />
        <xs:attribute name="rep" default="norepeat">
            <xs:simpleType>
                <xs:restriction base="xs:token">
                    <xs:enumeration value="norepeat" />
                    <xs:enumeration value="repeat" />
                </xs:restriction>
            </xs:simpleType>
        </xs:attribute>
        <xs:attribute name="choice" default="opt">
            <xs:simpleType>
                <xs:restriction base="xs:token">
                    <xs:enumeration value="opt" />
                    <xs:enumeration value="plain" />
                    <xs:enumeration value="req" />
                </xs:restriction>
            </xs:simpleType>
        </xs:attribute>
    </xs:complexType>
</xs:element>