<https://flammlin.com/blog/2013/12/06/%d0%bf%d1%80%d0%be%d0%b1%d0%b5%d0%b3/#breadcrumb>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://flammlin.com/blog/2013/12/06/%D0%BF%D1%80%D0%BE%D0%B1%D0%B5%D0%B3/>