<https://af-course.com/category/%e3%83%9e%e3%83%8d%e3%83%bc%e5%85%a8%e8%88%ac/%e3%83%aa%e3%82%b9%e3%82%af%e3%81%ab%e5%82%99%e3%81%88%e3%82%8b/%e8%80%81%e5%be%8c%e3%81%ab%e5%82%99%e3%81%88%e3%82%8b/#listItem>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://af-course.com/category/%E3%83%9E%E3%83%8D%E3%83%BC%E5%85%A8%E8%88%AC/%E3%83%AA%E3%82%B9%E3%82%AF%E3%81%AB%E5%82%99%E3%81%88%E3%82%8B/%E8%80%81%E5%BE%8C%E3%81%AB%E5%82%99%E3%81%88%E3%82%8B/>