<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>
<http://pop.h-cdn.co/assets/cm/15/06/320x426/54cfd37d513f7_-_math-museum-06-1212-de.jpg>
<http://www.popularmechanics.com/technology/g1020/6-ways-to-expand-your-mind-at-the-math-museum/>