<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>
<http://pop.h-cdn.co/assets/cm/15/05/320x240/54cb0c1b719bf_-_knuckleball-04-0413-de.jpg>
<http://www.popularmechanics.com/adventure/sports/g1164/anatomy-of-a-knuckleball/>