<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>
<http://ichef.bbci.co.uk/news/560/media/images/59132000/jpg/_59132691_c0016567-hydroelectric_power_station,_wales-spl.jpg>
<http://www.bbc.co.uk/news/science-environment-17404438>