Hammer, M. J., & Viessman, W. (1985). Water supply and pollution control (Ed.4.).
Dyfyniad Arddull ChicagoHammer, Mark J., and Warren Viessman. Water Supply and Pollution Control. Ed.4. New York, Harpor Collins, 1985.
Dyfyniad MLAHammer, Mark J., and Warren Viessman. Water Supply and Pollution Control. Ed.4. 1985.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.