<https://ikeda.dososhin.com/2014/11/#listItem>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://ikeda.dososhin.com/2014/11/16/%E7%B6%9A%E3%80%80%E3%83%9C%E3%83%84%E3%83%AF%E3%83%8A%E7%B4%80%E8%A1%8C/>