<https://smdd.seehua.com/%e7%b4%a0%e8%8a%8b%e8%8f%87%e9%b1%bc%e3%80%90%e8%9b%8b%e7%b4%a0-%e7%ba%af%e7%b4%a0%e3%80%91/>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://smdd.seehua.com/%E7%B4%A0%E8%8A%8B%E8%8F%87%E9%B1%BC%E3%80%90%E8%9B%8B%E7%B4%A0-%E7%BA%AF%E7%B4%A0%E3%80%91/>