RIDGLEY, D. C. (1938). Influence Of Geographiiiy On Our Economic Life Douglas C. Ridgley And Sidney E. Ekblaw. The Gregg.
Lua i Stíl Chicago (17ú heag.)RIDGLEY, Douglas C. Influence Of Geographiiiy On Our Economic Life Douglas C. Ridgley And Sidney E. Ekblaw. The Gregg, 1938.
Lua MLA (8ú heag.)RIDGLEY, Douglas C. Influence Of Geographiiiy On Our Economic Life Douglas C. Ridgley And Sidney E. Ekblaw. The Gregg, 1938.
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