<https://wilsonwu1974.pixnet.net/blog/post/99945547-%ef%b9%9d%e6%a1%83%e5%9c%92%e5%a4%a7%e6%ba%aa%e9%81%8a%e8%a8%98%ef%b9%9e%e6%85%88%e6%b9%96%e8%b3%9e%e3%80%8c%e6%a5%93%e3%80%8d%e7%b4%85>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://wilsonwu1974.pixnet.net/blog/post/99945547>