https://this.kiji.is/226439326585487363

http://www3.nhk.or.jp/news/html/20170417/k10010951721000.html

https://news.yahoo.co.jp/byline/yanaihitofumi/20170416-00069982/

https://www.buzzfeed.com/kazukiwatanabe/20170417-1?utm_term=.piWkoKQdG#.wiJDvV2No

http://www.moj.go.jp/content/001222823.pdf