<?xml version="1.0"?> <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"> <xs:complexType name="length1"> <xs:simpleContent> <xs:extension base="xs:nonNegativeInteger"> <xs:attribute name="unit" type="xs:NMTOKEN"/> </xs:extension> </xs:simpleContent> </xs:complexType> <xs:element name="width" type="length1"/> </xs:schema>