Slow sand filter maintenance :
costs and effects on water quality /
Raymond D. Letterman and Thomas R. Cullen, Jr.
APA Citation
Letterman, R. D., Cullen, T. R., Water Engineering Research Laboratory. (1985). Slow sand filter maintenance: costs and effects on water quality. Cincinnati, OH: U.S. Environmental Protection Agency, Water Engineering Research Laboratory.
MLA Citation
Letterman, Raymond D, Thomas R Cullen, and Water Engineering Research Laboratory. Slow Sand Filter Maintenance: Costs And Effects On Water Quality. Cincinnati, OH: U.S. Environmental Protection Agency, Water Engineering Research Laboratory, 1985.
Warning: These citations may not always be complete (especially for serials).