<https://www.ofa999.net/post/\u4E16\u754C\u76C3\u8DB3\u7403\u7279\u8F2F-38>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://www.ofa999.net/post/%E4%B8%96%E7%95%8C%E7%9B%83%E8%B6%B3%E7%90%83%E7%89%B9%E8%BC%AF-38>