<!– 3.2.3 : 3.2

If ref is present, then all of <simpleType>, form and type must be absent
This one tests "type"

–> <schema xmlns=“www.w3.org/2001/XMLSchema” targetNamespace=“foo” xmlns:foo=“foo”>

<element name="foo">
        <complexType>
              <attribute ref="foo:bar" type="string"/>                        
        </complexType>    
</element>  

<attribute name="bar" type="string"/>

</schema>