<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>
<http://ichef.bbci.co.uk/news/560/media/images/76756000/jpg/_76756839_comet_on_4_august_2014_-_navcam.jpg>
<http://www.bbc.com/news/science-environment-28659783>