<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>
<http://ichef.bbci.co.uk/news/ws/560/amz/worldservice/live/assets/images/2016/03/18/160318165622_toxico_4_640x360_thinkstock_nocredit.jpg>
<http://www.bbc.com/mundo/especial/vert_aut/2016/03/160318_vert_olor_autos_salud_yv>