<https://kaneda-mitsuru.com/2019/11/22/%e3%82%b2%e3%83%bc%e3%83%a0%e3%82%a2%e3%83%97%e3%83%aa%e3%81%ae%e7%8a%b6%e6%b3%81%e3%80%802019%e5%b9%b411%e6%9c%88/>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://kaneda-mitsuru.com/2019/11/22/%E3%82%B2%E3%83%BC%E3%83%A0%E3%82%A2%E3%83%97%E3%83%AA%E3%81%AE%E7%8A%B6%E6%B3%81%E3%80%802019%E5%B9%B411%E6%9C%88/>