<https://www.neobrass.com/post/10\u67085\u65E5\u7DF4\u7FD2\u65E5\u8A18>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://www.neobrass.com/post/10%E6%9C%885%E6%97%A5%E7%B7%B4%E7%BF%92%E6%97%A5%E8%A8%98>