<http://schema.org/about>
"For evidence that grassroots activism works, look no further than writer and climate activist Bill McKibben, who has spent the past year tirelessly knocking on doors with his climate crew over at 350.org. But as McKibben writes this week, door-knocking"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.treehugger.com/corporate-responsibility/news-from-mother-jones-450-ppm-aint-gonna-cut-it.html>