<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>
<http://hbu.h-cdn.co/assets/cm/15/04/980x1254/54c098737c0fd_-_05-hbx-hang-picture-in-hallway-0207-s2.jpg>
<http://www.housebeautiful.com/home-remodeling/interior-designers/how-to/g1328/picture-hanging-tips/>