http://www.itmedia.co.jp/mobile/articles/1301/16/news102.html

http://kounomaki.blog84.fc2.com/blog-entry-615.html

http://www.nikkei.com/article/DGXNASFD1701M_X10C13A1CN8000/

http://toyokeizai.net/articles/-/12515

http://kanpou.npb.go.jp/20130117/20130117g00009/20130117g000090000f.html

http://mainichi.jp/select/news/20130118k0000m040097000c.html