Birdsall, S. S., & Florin, J. (1992). Outline of american geography: Regional landscapes of the united states (Fourth edition.). John Wiley.
Chicago Style (17. basım) AtıfBirdsall, Stephen S., ve John Florin. Outline of American Geography: Regional Landscapes of the United States. Fourth edition. New York: John Wiley, 1992.
MLA (9th ed.) AtıfBirdsall, Stephen S., ve John Florin. Outline of American Geography: Regional Landscapes of the United States. Fourth edition. John Wiley, 1992.
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