<https://oyakoeigo.com/2015/12/09/%e8%8b%b1%e8%aa%9e%e3%82%b9%e3%82%bf%e3%83%bc%e3%83%88%e3%81%af0%e6%ad%b3%e3%81%8b%e3%82%89%ef%bc%81/#primaryimage>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://oyakoeigo.com/2015/12/09/%E8%8B%B1%E8%AA%9E%E3%82%B9%E3%82%BF%E3%83%BC%E3%83%88%E3%81%AF0%E6%AD%B3%E3%81%8B%E3%82%89%EF%BC%81/>