1. Circular No. 198;Ruehle,1931
2. Assay Methods of Antibiotics, A Laboratory Manual;Donald C,1955
3. "B. Mycoides Cup Plate Method for Determination of Chlortetracycline, Tetracycline and Oxytetracycline Concentrations in Serum and Body Fluids" Copy, Department of Health, Washington 25, D. C.
4. J.Immunology;Strauss,1941
5. This Journal;Naimark,1954