EPA, U. (1994). HANDBOOK OF GROUND WATER: V-1: GROUND WATER AND CONTAMINATION.
Dyfyniad Arddull ChicagoEPA, US. HANDBOOK OF GROUND WATER: V-1: GROUND WATER AND CONTAMINATION. JODHPUR, SCIENTIFIC PUBLISHERS, 1994.
Dyfyniad MLAEPA, US. HANDBOOK OF GROUND WATER: V-1: GROUND WATER AND CONTAMINATION. 1994.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.