<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>
<http://ghk.h-cdn.co/assets/cm/15/11/980x632/54ff06be186e8-ghk-skip-crunches-2-s2.jpg>
<http://www.goodhousekeeping.com/health/fitness/g596/dangerous-exercises/>