1. American Heart Association (1926). Amer. Heart J., 2, 202.
2. Blumgart, H. (1924). Heart, 11, 49.
3. Gold, H., Kwit, N. T., Otto, H., and Fox, T. (1939). J. Pharmacol., 67, 224.
4. The Pharmacological Basis of Therapeutics;Goodman, L.; Gilman, A.,1941
5. Knox, J. A. C. (1940). Brit. Heart J., 2, 289.