Plan 9 from Bell Labs’s /usr/web/sources/contrib/fernan/nhc98/src/libraries/HaXml/tests/xml-conformance/ibm/invalid/P56/out/ibm56i06.xml
<tokenizer> <a first="AC1999" second="BC1999"></a> This is a Negative validity test for ID. There is more than attribute of type ID for the element a </tokenizer>
