1. "The Merck Index",1968
2. M. Bockmuhl, “Medicine In Its Chemical Aspects,” Reports from the Medico-Chemical Research Laboratories of the I.G. Farbenindustrie Abetiengesellschaft, Leverkusen, Germany.
3. S. Erbe, East Ger. pat. 41,306 (Cl. A61k) (Sept. 5, 1965).
4. Sulfurous Acid Salts as Pharmaceutical Antioxidants