Plan 9 from Bell Labs’s /usr/web/sources/contrib/fernan/nhc98/src/libraries/HaXml/tests/xml-conformance/ibm/not-wf/P29/ibm29n03.xml
<?xml version="1.0" encoding='UTF-8'?> <!DOCTYPE animal [ <!ELEMENT animal ANY> <!ENTITY % parameterE "color"> <!ATTLIST animal %parameterE; CDATA #IMPLIED> ]> <!-- Parameter reference appears inside AttlistDecl in DTD --> <animal>Any content</animal>