<http://schema.org/about>
"For the 100 or so mayors who attended the two-day bipartisan Climate Protection Summit last week, the message was clear: The cities of the future have to be walkable, workable, livable, and sustainable."^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.treehugger.com/corporate-responsibility/us-mayors-told-cities-future-has-to-be-green.html>