<http://schema.org/about>
"Before you go dipping your toes in the first lake or river you come across this summer, make sure it's not on our list of the world's dirtiest lakes and rivers."^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.treehugger.com/natural-sciences/worlds-nastiest-lakes-and-rivers-slideshow.html>