Spengler, J. J. (1961). Natural resources and economic growth: Papers presented at a conference held at Ann Arbor, Michigan, April 7-9, 1960. Washington, D.C: Resources for the Future.
Παραπομπή Chicago StyleSpengler, Joseph J. Natural Resources and Economic Growth: Papers Presented At a Conference Held At Ann Arbor, Michigan, April 7-9, 1960. Washington, D.C: Resources for the Future, 1961.
Παραπομπή MLASpengler, Joseph J. Natural Resources and Economic Growth: Papers Presented At a Conference Held At Ann Arbor, Michigan, April 7-9, 1960. Washington, D.C: Resources for the Future, 1961.
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