American Public Health Association, American Water Works Association, Water Environment Federation, Greenberg, A. E., Clesceri, L. S., & Eaton, A. D. (1992). Standard methods for the examination of water and wastewater (18th ed.). American Public Health Association.

American Public Health Association, American Water Works Association, Water Environment Federation, Arnold E. Greenberg, Lenore S. Clesceri, and Andrew D. Eaton. Standard Methods for the Examination of Water and Wastewater. 18th ed. Washington, DC: American Public Health Association, 1992.

American Public Health Association, et al. Standard Methods for the Examination of Water and Wastewater. 18th ed. American Public Health Association, 1992.