<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>
<http://pop.h-cdn.co/assets/cm/15/06/54d0e9a60eeb7_-_rusty_bolt_04_0510-lg.jpg>
<http://www.popularmechanics.com/home/how-to/a5754/how-to-free-a-rusted-bolt/>