<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>
<http://rbk.h-cdn.co/assets/cm/14/50/980x1278/548a6f9925037_-_rbk-vitamins-you-need-calcium-s2.jpg>
<http://www.redbookmag.com/body/health-fitness/advice/g1331/what-vitamins-supplements-should-i-take/>