Harr, M. E. (1962). Groundwater and seepage. McGraw-Hill.
Dyfyniad Arddull ChicagoHarr, Milton Edward. Groundwater and Seepage. New York: McGraw-Hill, 1962.
Dyfyniad MLAHarr, Milton Edward. Groundwater and Seepage. McGraw-Hill, 1962.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.