<https://hk.sanshuizy.com/book/sort_4_1.html>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://hk.sanshuizy.com/%E5%A4%A7%E6%98%8E%EF%BC%9A%E6%88%91%EF%BC%8C%E8%AA%BF%E6%95%99%E6%9C%A8-419065/>