<http://schema.org/about>
"Twitter is getting to be a great resource for charities and eco-activism, proven by the success of charity:water's twestival, earthtweet, and tweeting congress. Here's another great chance to use Twitter as a force of good. Plant"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.treehugger.com/clean-technology/twittering-for-trees-and-world-environment-day.html>