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2. APHA. 1985 . Standard Methods for the Examination of Water and Wastewater, 16th Ed. APHA, AWWA and WPCF, Washington, D.C.
3. A. W. BRANT, J. W. GOBLE, J. A. HAMANN, C. J. WABECK, and R. E. WALTERS, 1982 . Guidelines for Establishing and Operating Broiler Processing Plants. U.S. Dept. Agric. Agricultural Research Service. Agriculture Handbook No. 581.
4. EPA. 1979 . Methods for Chemical Analysis of Water and Wastes. U.S. Environmental Protection Agency, publication EPA-600/4-79-020.
5. U.S. GOV1987 . Code of Federal Regulations, Title 9, Section 381.66.