<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>
<http://ichef.bbci.co.uk/news/ws/560/amz/worldservice/live/assets/images/2014/06/20/140620111042_thinking_man_in_bed_304x171_thinkstock_nocredit.jpg>
<http://www.bbc.com/mundo/noticias/2014/06/140619_vert_fut_mitos_medicos_realmente_hombres_piensan_sexo_finde_yv.shtml>