Fair, G. M., Geyer, J. C., & Okun, D. A. (1971). Elements of water supply and wastewater disposal. Wiley.
Dyfyniad Arddull ChicagoFair, Gordon Maskew, John Charles Geyer, and Daniel Alexander Okun. Elements of Water Supply and Wastewater Disposal. New York: Wiley, 1971.
Dyfyniad MLAFair, Gordon Maskew, et al. Elements of Water Supply and Wastewater Disposal. Wiley, 1971.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.