<https://forum.audio.com.pl/topic/56894-zestaw-20-do-salonu-ok-30m2-do-5000z%C5%82/#comment-237694>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://forum.audio.com.pl/topic/56894-zestaw-20-do-salonu-ok-30m2-do-5000z%C5%82/>