<https://www.arisa-crystal.com/%e2%91%a2-%e3%82%bb%e3%83%a9%e3%83%94%e3%82%b9%e3%83%88%e8%ac%9b%e5%ba%a7/#webpage>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://www.arisa-crystal.com/%E2%91%A2-%E3%82%BB%E3%83%A9%E3%83%94%E3%82%B9%E3%83%88%E8%AC%9B%E5%BA%A7/>