Plan 9 from Bell Labs’s /usr/web/sources/contrib/fernan/nhc98/src/libraries/HaXml/tests/xml-conformance/ibm/not-wf/P65/ibm65n01.xml
<?xml version="1.0"?> <!-- syntax test for Production 65--> <!DOCTYPE animal SYSTEM "ibm65n01.dtd" [ <!ELEMENT animal ANY> ]> <animal> Negative Test. Pattern1.Illegal sequence of ']]' </animal>