<http://www.w3.org/1999/xhtml/vocab#menuitemcheckbox>	<http://www.w3.org/2007/05/powder-s#describedby>	<http://demo.openlinksw.com/about/id/entity/http/www.w3.org/1999/xhtml/vocab> .
<http://www.w3.org/1999/xhtml/vocab#menuitemcheckbox>	<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>	<http://www.w3.org/1999/02/22-rdf-syntax-ns#Property> .
<http://www.w3.org/1999/xhtml/vocab#menuitemcheckbox>	<http://www.w3.org/2000/01/rdf-schema#comment>	"A\n      checkable menuitem that has three possible values: true, false, or mixed."^^<http://www.w3.org/2001/XMLSchema#string> .