1. AMERICAN PUBLIC HEALTH ASSOCIATION, AMERICAN WATER WORKS ASSOCIATION, WATER POLLUTION CONTROL FEDERATION: Standard methods for the examination of water and wastewater. 14 ed. Washington, D.C.: APHA 1975.
2. BUIKEMA, A. L., JR., D. R. LEE, and J. CAIRNS, JR.: J. Test. Eval.4(2), 119 (1976).
3. CAIRNS, J., JR., and K. L. DICKSON: J. Test. Eval.6(2), 81 (1978).
4. STP 657,1978
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