ZIMMERMANN, E. W. (1951). World Resources and Industries: A fungtional appraisal of the availability of agricultural and industrial materials. Harper & Brothers Publishers.
Chicago-viite (17. p.)ZIMMERMANN, Erich W. World Resources and Industries: A Fungtional Appraisal of the Availability of Agricultural and Industrial Materials. Harper & Brothers Publishers, 1951.
MLA-viite (8. p.)ZIMMERMANN, Erich W. World Resources and Industries: A Fungtional Appraisal of the Availability of Agricultural and Industrial Materials. Harper & Brothers Publishers, 1951.
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