Keith, L. H. (1988). Principles of environmental sampling. American Chemical Society.
Dyfyniad Arddull ChicagoKeith, Lawrence H. Principles of Environmental Sampling. Washington, D.C: American Chemical Society, 1988.
Dyfyniad MLAKeith, Lawrence H. Principles of Environmental Sampling. American Chemical Society, 1988.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.