<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>
<http://www.bbc.com/mundo/noticias/2014/05/140512_body_clock_interactive_vj.shtml>
<http://www.bbc.com/mundo/noticias/2014/05/140512_body_clock_interactive_vj.shtml>