<https://frontera.ru/forums/topic/4555-%D1%88%D1%80%D1%83%D1%81%D1%8B/#comment-53892>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://frontera.ru/forums/topic/4555-%D1%88%D1%80%D1%83%D1%81%D1%8B/>