http://www.osaka-up.or.jp/books/ISBN978-4-87259-507-9.html

http://news.livedoor.com/article/detail/12351237/

http://kanz.jp/hanrei/detail/86283/

http://www.npa.go.jp/topics/kyuukou/tyouikinannai.pdf

http://www.jiji.com/jc/article?k=2016113000712&g=soc http://www.nichibenren.or.jp/library/ja/opinion/report/data/2016/opinion_161115_3_01.pdf http://www.nichibenren.or.jp/activity/document/opinion/year/2016/161115_3.html