Harris, A., Harrison, C., & Smithson, P. (1972). The land and conservation. Grosset and Dunlap.
Dyfyniad Arddull ChicagoHarris, Anne, Carolyn Harrison, and Peter Smithson. The Land and Conservation. New York: Grosset and Dunlap, 1972.
Dyfyniad MLAHarris, Anne, et al. The Land and Conservation. Grosset and Dunlap, 1972.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.