1. American Petroleum Institute, Research Project 44 and the Manufacturing Chemists Association Research Project, located at Department of Chemistry of the Agricultural and Mechanical College of Texas, College Station, Texas.
2. Barnard, D., Fabian, J.M., and Koch, H.P., J. Chem. Soc. 1949, 2442.
3. Bell, P.H. and Roblin, R.O., Jr., J. Am. Chem. Soc. 64, 2905 (1942).
4. Carol, J., Ann. N.Y. Acad. Sci. 69, Art. 1, 190 (1957).
5. Chapman, D.I. and Moss, M.S. in Isolation and Identification of Drugs ( E.G.C. Clarke, ed.) The Pharmaceutical Press, London, 1969, p. 103.