Plan 9 from Bell Labs’s /usr/web/sources/contrib/fernan/nhc98/src/libraries/HaXml/tests/xml-conformance/ibm/not-wf/P45/ibm45n05.xml
<?xml version="1.0"?> <!DOCTYPE root [ <!ELEMENT root (#PCDATA)> <!--* Mising Name S contentspec in elementdecl *--> <!ELEMENT > ]> <root>Any content</root>