<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>
<http://pop.h-cdn.co/assets/cm/15/05/54ca6fb72cc73_-_rock-blast-5-0808-70000539.jpg>
<http://www.popularmechanics.com/home/outdoor-projects/how-to/a3443/4274976/>