Plan 9 from Bell Labs’s /usr/web/sources/contrib/fernan/nhc98/src/libraries/HaXml/tests/xml-conformance/eduni/namespaces/1.1/004.xml
<?xml version="1.1"?> <!-- 1.1 style prefix unbinding and rebinding --> <foo xmlns:a="http://example.org/namespace"> <bar xmlns:a=""> <foo xmlns:a="http://example.org/other-namespace" a:attr="1"/> </bar> </foo>