<?xml version="1.0"?> <page> <!-- valid xs:date --> <date date="0001-12-31Z"/> <date date="3000-01-31"/> <date date="2000-02-29"/> <date date="9990001-12-31Z"/> <date date="-0004-02-29"/> <date date="1999-01-02"/> <date date="1999-01-03"/> <date date="2004-01-01"/> <date date="2006-01-01"/> <date date="2007-12-31"/> </page>