1. BAILEY, N.T.J.:Statistical Methods in Biology. English Universities Press, Ltd., London, England (1959).
2. BREIDENBACH, A., LICHTENBERG, J., HENKE, C. F., SMITH, D. J., EICHELBERGER, J. W. AND STIERLI, H.:The Identification and Measurement of Chlorinated Hydrocarbon Pesticides in Surface Waters. U. S. Government Printing Office: 1968-0-315-824.
3. KAHN, L. and WAYMAN, C. H.: Anal. Chem.36, 1340 (1964).
4. U. S. Public Health Service (Region VII): Community Water Supply Study, New Orleans, Louisiana Standard Metropolitan Statistical Area (August, 1970).