Plan 9 from Bell Labs’s /usr/web/sources/contrib/fernan/nhc98/src/libraries/HaXml/tests/xml-conformance/ibm/valid/P56/out/ibm56v05.xml
<tokenizer> <a first="AC1999"></a> <b second="CD345"></b> This is a positive validity test for ID. any element type has no more than one attribute of type ID specified </tokenizer>