Weizsacker, E. V. E. (2005). Factor four: Doubling wealth, haling resource use. Earthscan.
Chicago Edition CitationWeizsacker, Ernst Von Etc. Factor Four: Doubling Wealth, Haling Resource Use. London: Earthscan, 2005.
Deismireacht MLAWeizsacker, Ernst Von Etc. Factor Four: Doubling Wealth, Haling Resource Use. Earthscan, 2005.
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