Wratten, S. D. (1980). Field and laboratory exercises in ecology. London: Arnold.
Dyfyniad Arddull ChicagoWratten, Stephen D. Field and Laboratory Exercises in Ecology. London: Arnold, 1980.
Dyfyniad MLAWratten, Stephen D. Field and Laboratory Exercises in Ecology. London: Arnold, 1980.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.