<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>
<http://ichef-1.bbci.co.uk/news/560/media/images/75866000/jpg/_75866726_t1220086-willow_grown_for_bioenergy-spl(1).jpg>
<http://www.bbc.com/news/science-environment-28041525>