<http://schema.org/about>
"We're all familiar with the concept of negative externalities: the behavior of one person has negative impacts on another person (or society as a whole), yet the person causing those impacts doesn't pay for them.  Writing about this concept as it applies"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.treehugger.com/cars/pay-as-you-drive-payd-insurance-a-way-to-address-negative-externalities.html>