Dyfyniad APA

Field, R. M. (1936). Natural resources of the United States: A basics for economic Geography. New York: Barnes and Noble.

Dyfyniad Arddull Chicago

Field, Richard M. Natural Resources of the United States: A Basics for Economic Geography. New York: Barnes and Noble, 1936.

Dyfyniad MLA

Field, Richard M. Natural Resources of the United States: A Basics for Economic Geography. New York: Barnes and Noble, 1936.

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