https://1pg.jp/2018/01/post-1241/

https://www3.nhk.or.jp/news/html/20180119/k10011295051000.html

http://www.sankei.com/smp/affairs/news/180120/afr1801200016-s1.html

https://headlines.yahoo.co.jp/hl?a=20180120-00000014-at_s-l22

https://www.nichibenren.or.jp/activity/document/statement/year/2017/171227.html