Plan 9 from Bell Labs’s /usr/web/sources/contrib/fernan/nhc98/src/libraries/HaXml/tests/xml-conformance/ibm/xml-1.1/not-wf/P77/ibm77n19.xml
<?xml version='1.1' encoding='UTF-8'?> <!DOCTYPE root SYSTEM "ibm77n19.dtd"> <root>&e;</root>