<https://mes-academy.com/blog/%e3%80%90%e3%81%a1%e3%82%87%e3%81%a3%e3%81%a8%e6%89%8b%e4%bc%9d%e3%81%a3%e3%81%a6%e3%82%82%e3%82%89%e3%81%86%e3%81%93%e3%81%a8%e3%80%91%e3%81%93%e3%81%93%e3%81%8c%e9%87%8d%e8%a6%81/>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://mes-academy.com/blog/%E3%80%90%E3%81%A1%E3%82%87%E3%81%A3%E3%81%A8%E6%89%8B%E4%BC%9D%E3%81%A3%E3%81%A6%E3%82%82%E3%82%89%E3%81%86%E3%81%93%E3%81%A8%E3%80%91%E3%81%93%E3%81%93%E3%81%8C%E9%87%8D%E8%A6%81/>