<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>
<http://wdy.h-cdn.co/assets/cm/15/10/480x552/54f5fdb039127_-_chalkboard-calculation-xl.jpg>
<http://www.womansday.com/relationships/sex-tips/advice/g1204/how-to-have-more-sex/>