Gumerman, R. C., Burris, B. E., & Hansen, S. P. (1986). Small water system treatment costs. Noyes Data Corporation.
Chicago Style (17th ed.) ZitazioaGumerman, Robert C., Bruce E. Burris, eta Sigurd P. Hansen. Small Water System Treatment Costs. Park Ridge: Noyes Data Corporation, 1986.
MLA (9th ed.) ZitazioaGumerman, Robert C., et al. Small Water System Treatment Costs. Noyes Data Corporation, 1986.
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