Plan 9 from Bell Labs’s /usr/web/sources/contrib/fernan/nhc98/src/libraries/HaXml/tests/xml-conformance/ibm/valid/P64/ibm64v01.xml
<?xml version="1.0"?> <!-- syntax test for Production 64--> <!DOCTYPE animal SYSTEM "ibm64v01.dtd" [ <!ELEMENT animal ANY> ]> <animal> Positive Test. Pattern1 </animal>