Plan 9 from Bell Labs’s /usr/web/sources/contrib/fernan/nhc98/src/libraries/HaXml/tests/xml-conformance/ibm/valid/P09/student.dtd
<?xml encoding="utf-8"?> <!-- student.dtd --> <!ENTITY combine "My Name is %FullName; and my age is &Age; Again %FullName; %FullName; and my status is &Status; &Status; and %FullName; &Age; %FullName; &Status; That is all.">