<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>
<http://ichef.bbci.co.uk/news/ws/560/amz/worldservice/live/assets/images/2014/04/22/140422060020_fidel_castro_304x171_ap.jpg>
<http://www.bbc.com/mundo/noticias/2014/05/140416_eeuu_television_retirada_barbara_walters_entrevistas_jg.shtml>