<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>
<http://ichef-1.bbci.co.uk/news/ws/560/amz/worldservice/live/assets/images/2011/12/09/111209184650_triangulo_bermudas_304x171_usnavy_nocredit.jpg>
<http://www.bbc.com/mundo/noticias/2016/03/160314_ciencia_crater_mar_barents_clave_misterio_triangulo_bermudas_lv>