<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<http://schema.org/WebSite>
<http://osc.org/index.php?option=com_content&view=article&id=242:if-liquid-nitrogen-is-so-cold-why-does-it-boil&catid=14:science-live&Itemid=56&layout=default&date=2013-06-01>