<http://schema.org/about>
"In addition to emissions originating within a nation's borders in assessing progress on mitigating a nation's climate impact, as with personal impact, the emissions of all goods consumed need to be included."^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.treehugger.com/environmental-policy/why-we-should-talking-national-carbon-footprint-not-just-carbon-emissions.html>