<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>
<http://pop.h-cdn.co/assets/cm/15/05/54caaccc7b908_-_caveman-hunting-photo-de.jpg>
<http://www.popularmechanics.com/adventure/outdoors/a6023/how-to-hunt-like-a-caveman/>