<https://www.long-tail-express.com/%e3%83%aa%e3%83%9d%e3%83%89%e3%83%aa%e3%83%b3_od/#webpage>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://www.long-tail-express.com/%E3%83%AA%E3%83%9D%E3%83%89%E3%83%AA%E3%83%B3_od/>