http://www111.sakura.ne.jp/~hanyan/todouhuken/index.html

http://diary.nttdata.co.jp/diary2004/05/20040509.html

http://www.yomiuri.co.jp/business/news/20040509i412.htm

http://health.nikkei.co.jp/news/top/topCh.cfm?id=20040506e001y40006

http://www.daily-tohoku.co.jp/kakono_n/kako040508.htm

http://www.sanyo.oni.co.jp/34news/2004/05/09/20040509105439.html

http://www.kobe-np.co.jp/chiiki/hanshin04/0509jl14690.html

http://www.mainichi-msn.co.jp/kagaku/env/news/20040510k0000e040011000c.html

http://www.agara.co.jp/DAILY/20040511/20040511_003.html

http://pcweb.mycom.co.jp/news/2004/05/10/012.html

http://www.yomiuri.co.jp/science/news/20040510ic01.htm