<http://schema.org/about>
"There's little agreement on exactly how and when the world as we know it will end, but there are plenty of theories out there."^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.mnn.com/earth-matters/wilderness-resources/photos/11-ways-the-world-as-we-know-it-could-end/road-to>