<https://news.yahoo.co.jp/articles/d2dc5128f20f96d08a42d3cd9c5b1edb90b76081>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://news.yahoo.co.jp/articles/d2dc5128f20f96d08a42d3cd9c5b1edb90b76081>