<https://atsushi-kanda.com/#organization>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://atsushi-kanda.com/theory-key/%E3%83%89%E3%83%AC%E3%83%9F%E3%83%95%E3%82%A1%E3%82%BD%E3%83%A9%E3%82%B7>