<https://www.dowakougyo.com/post/\u30D6\u30ED\u30B0\u30BF\u30A4\u30C8\u30EB>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://www.dowakougyo.com/post/%E3%83%96%E3%83%AD%E3%82%B0%E3%82%BF%E3%82%A4%E3%83%88%E3%83%AB>