<https://secure.gravatar.com/avatar/2ba2562f007c44c4da883a3b5156df6b?s=96&d=mm&r=g>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://www.digielias.cz/nesetrete-na-porizeni-nouzoveho-osvetleni/>