<https://www.suginamikikai.jp/single-post/2020/06/23/\u907F\u96E3\u8A13\u7DF4>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://www.suginamikikai.jp/single-post/2020/06/23/%E9%81%BF%E9%9B%A3%E8%A8%93%E7%B7%B4>