<https://ms-yamada.jp/education/%e7%99%87%e7%99%aa%e6%8c%81%e3%81%a1%e3%81%ae%e5%ad%90%e3%81%ab%e3%82%aa%e3%82%b9%e3%82%b9%e3%83%a1%ef%bc%81%ef%bc%81/>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://ms-yamada.jp/education/%E7%99%87%E7%99%AA%E6%8C%81%E3%81%A1%E3%81%AE%E5%AD%90%E3%81%AB%E3%82%AA%E3%82%B9%E3%82%B9%E3%83%A1%EF%BC%81%EF%BC%81/>