<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>
<http://ichef-1.bbci.co.uk/news/560/media/images/70435000/jpg/_70435518_m1320644-lung_cancer_cell_division,_sem-spl.jpg>
<http://www.bbc.com/news/health-24493862>