1. Anon, Tentative Methods for the Determination of Antibiotics in Milk. Revised August 1958 (Food and Drug Administration, Washington, D.C.).
2. Standard Methods for the Examination of Dairy Products, seventh ed., 185 (American Public Health Association, Inc., New York, 1960).
3. Cerny, J., and Morris, R. L. A., J. Milk and Food Tech., 18, 281 (1955).
4. Kosikowski, F. V., and Mocquot, G. A., Intern. Dairy Congr. Proc., 3, 203 (1956).
5. Foster, J. W., and Woodruff, H. B., J. Bact., 46, 187 (1943).