+ <xs:element name="modification">
+ <xs:complexType>
+ <xs:simpleContent>
+ <xs:extension base="xs:string">
+ <xs:attribute name="id" type="xs:nonNegativeInteger" />
+ <xs:attribute name="date" type="xs:date" />
+ </xs:extension>
+ </xs:simpleContent>
+ </xs:complexType>