<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>
<http://pop.h-cdn.co/assets/cm/15/05/480x276/54cb5c3e0fee8_-_dubike-10-1114-lgn.jpg>
<http://www.popularmechanics.com/adventure/sports/g1693/baidu-developing-china-smartbike/>