<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>
<http://pop.h-cdn.co/assets/cm/15/05/480x360/54cb07819f49f_-_rotary-hammer-test-06-0113-lgn.jpg>
<http://www.popularmechanics.com/home/tools/reviews/g1072/tool-test-top-cordless-rotary-hammers/>