<https://www.ayudadeblogger.com/2015/10/solucion-4-error-al-analizar-xml-signo-menor-que.html>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://www.ayudadeblogger.com/2015/10/solucion-4-error-al-analizar-xml-signo-menor-que.html>