<http://schema.org/about>
"This weekend, San Francisco held Green Festival, the nation's largest green consumer living event. Over 40,000 people packed into the Concourse Exhibition Center to see over 350 businesses, artists, nonprofits, and over 125"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.treehugger.com/culture/san-francisco-green-festival-2009-shows-how-a-true-green-event-should-be-run.html>