http://keizaigaku.seesaa.net/article/2828566.html
と
http://keizaigaku.seesaa.net/article/2875933.html
http://keizaigaku.seesaa.net/article/2918116.html
http://keizaigaku.seesaa.net/article/4324761.html
http://www.asahi-net.or.jp/~tr8k-akym/hoiku.htm