Ehlers, V. M., & Steel, E. W. (1950). Municipal and rural sanitation. MacGraw-Hill.
Dyfyniad Arddull ChicagoEhlers, Victor Marcus, and Ernest William Steel. Municipal and Rural Sanitation. New York: MacGraw-Hill, 1950.
Dyfyniad MLAEhlers, Victor Marcus, and Ernest William Steel. Municipal and Rural Sanitation. MacGraw-Hill, 1950.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.