<https://talk.pr-cy.ru/topic/10120-vygodno-li-uchitsya-na-programmista/#comment-115905>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://talk.pr-cy.ru/topic/10120-vygodno-li-uchitsya-na-programmista/?tab=comments#comment-115950>