<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>
<http://hbu.h-cdn.co/assets/cm/15/04/320x368/54c0b67289806_-_03-hbx-interlocking-wood-staircase-netto-1011-xln.jpg>
<http://www.housebeautiful.com/room-decorating/entryway-ideas/tips/g1380/unique-staircases/>