RIDGLEY, D. C. (1938). Influence Of Geographiiiy On Our Economic Life Douglas C. Ridgley And Sidney E. Ekblaw. The Gregg.
Chicago-viite (17. p.)RIDGLEY, Douglas C. Influence Of Geographiiiy On Our Economic Life Douglas C. Ridgley And Sidney E. Ekblaw. The Gregg, 1938.
MLA-viite (8. p.)RIDGLEY, Douglas C. Influence Of Geographiiiy On Our Economic Life Douglas C. Ridgley And Sidney E. Ekblaw. The Gregg, 1938.
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