<https://msgolfblog.com/2019%e5%b9%b4%e5%9b%bd%e5%86%85%e7%94%b7%e5%ad%90%e3%83%84%e3%82%a2%e3%83%bc%e3%82%b7%e3%83%bc%e3%83%89%e9%81%b8%e6%89%8b/>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://msgolfblog.com/2019%E5%B9%B4%E5%9B%BD%E5%86%85%E7%94%B7%E5%AD%90%E3%83%84%E3%82%A2%E3%83%BC%E3%82%B7%E3%83%BC%E3%83%89%E9%81%B8%E6%89%8B/>