<https://secure.gravatar.com/avatar/4d7538860ee3a88bcfe1facd99080926?s=96&amp;d=mm&amp;r=g>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://happybikeshamburg.de/es/blog/alter-elbtunnel-hamburg-10-fakten/>