American Water Works Association, ebrary, Inc, Stubbart, J. M., Lauer, B., & McCandless, T. J. (2004). AWWA water operator field guide. American Water Works Association.
Chicago Style (17th ed.) ZitazioaAmerican Water Works Association, Inc ebrary, John M. Stubbart, Bill Lauer, eta Timothy J. McCandless. AWWA Water Operator Field Guide. Denver, Colo.: American Water Works Association, 2004.
MLA (9th ed.) ZitazioaAmerican Water Works Association, et al. AWWA Water Operator Field Guide. American Water Works Association, 2004.
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