<http://schema.org/about>
"With 7 billion people on the planet, things have already begun to feel a bit hot and crowded, particularly in swelling urban centers -- but researchers warn that we've ain't seen nothing yet."^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.treehugger.com/natural-sciences/urban-expansion-puts-humanity-risk.html>