Plan 9 from Bell Labs’s /usr/web/sources/contrib/fernan/nhc98/src/libraries/HaXml/tests/xml-conformance/ibm/valid/P56/out/ibm56v08.xml
<!DOCTYPE test [ <!NOTATION gif PUBLIC 'gif'> ]> <test> <landscape sun="image"></landscape> values of type ENTITY match the Name production and the ENTITY value matches the name of an unparsed entity declared in the DTD. </test>