<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>
<http://ichef-1.bbci.co.uk/news/560/media/images/68124000/jpg/_68124677_c0148937-dividing_liver_cancer_cell,_sem-spl.jpg>
<http://www.bbc.co.uk/news/health-22870352>