1. 1) Ministry of Health, Labour and Welfare, 〈http://www.mhlw.go.jp/kinkyu/diet/musyounin.html〉, cited 3 April, 2017.
2. 2) Ministry of Health, Labour and Welfare, Press release, 31 March, 2017. Results of the “Purchase Survey of Internet Sales Products” in FY2014 are announced, Drug ingredients were detected in half or more so-called dietary supplements: 〈http://www.mhlw.go.jp/file/04Houdouhappyou-11126000-Iyakushokuhinkyoku-Kanshishidoumayakutaisakuka/170331_press.pdf〉, cited 3 April, 2017.
3. 3) Ministry of Health, Labour and Welfare, Press release, 23 February, 2017. Alert for dietary supplements containing hidden drug ingredients: 〈http://www.mhlw.go.jp/file/04-Houdouhappyou-11126000-Iyakushokuhinkyoku-Kanshishidoumayakutaisakuka/170223_fukuoka-press_1.pdf〉, cited 3 April, 2017.
4. 4) Uchiyama N., Saisho K., Kikura-Hanajiri R., Haishima Y., Goda Y., Chem. Pharm. Bull., 56, 1331-1334 (2008).
5. 5) Demizu Y., Wakana D., Kamakura H., Kurihara M., Okuda H., Goda Y., Chem. Pharm. Bull., 59, 1314-1316 (2011).