De Bell, G. (1970). The environmental handbook / edited by Garrett De Bell. Ballantine Books.
Dyfyniad Arddull ChicagoDe Bell, Garrett. The Environmental Handbook / Edited by Garrett De Bell. New York: Ballantine Books, 1970.
Dyfyniad MLADe Bell, Garrett. The Environmental Handbook / Edited by Garrett De Bell. Ballantine Books, 1970.
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