<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>
<http://digitalspyuk.cdnds.net/12/21/showbiz_katy_perry_billboards_2012.jpg>
<http://www.digitalspy.com/showbiz/news/a386242/katy-perry-i-had-to-smile-through-the-tough-times-last-year/>