<https://nch.invisionzone.com/topic/28381-bot%C3%B3n-extraer-no-reacciona/#comment-79965>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://nch.invisionzone.com/topic/28381-bot%C3%B3n-extraer-no-reacciona/>