<http://schema.org/about>
"The mysterious fall of the largest of the world's earliest urban civilizations nearly 4,000 years ago in what is now India, Pakistan, Nepal and Bangladesh now a"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.mnn.com/earth-matters/climate-weather/stories/indus-valley-civilization-collapsed-because-of-climate-change>