1. 1) Ministry of Health, Labour and Welfare: <http://www.mhlw.go.jp/topics/medias/year/08/index.html#>, cited 15 March, 2010.
2. 2) Ministry of Health, Labour and Welfare: <http://hfnet.nih.go.jp/usr/kiso/pamphlet/ishimuke.pdf>, cited 10 March, 2010.
3. 3) National Institute of Health and Nutrition: <http://hfnet.nih.go.jp/contents/index1.html>, cited 25 March, 2010.
4. 4) Takemasa F., Chozai to Joho, 15, 84-90 (2009).