Παραπομπή APA

Colby, C. C., & Foster, A. (1940). Economic geography: Industries and resources of the commercial world. United States of America: United States of America Armed Forces.

Παραπομπή Chicago Style

Colby, Charles C., και Alice Foster. Economic Geography: Industries and Resources of the Commercial World. United States of America: United States of America Armed Forces, 1940.

Παραπομπή MLA

Colby, Charles C., και Alice Foster. Economic Geography: Industries and Resources of the Commercial World. United States of America: United States of America Armed Forces, 1940.

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