<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>
<http://ichef.bbci.co.uk/news/ws/560/amz/worldservice/live/assets/images/2012/09/12/120912154118_fumador_304x171_spl_nocredit.jpg>
<http://www.bbc.com/mundo/noticias/2012/09/120912_exposicion_fumar_memoria_men.shtml>