Plan 9 from Bell Labs’s /usr/web/sources/contrib/fernan/nhc98/src/libraries/HaXml/tests/xml-conformance/eduni/errata-2e/E60.xml

<?xml version="1.0"?>
<!DOCTYPE foo [
<!ELEMENT foo ANY>
<!ENTITY % e SYSTEM "E60.ent">
%e;
]>
<foo/>