Brigham, A. P. (1903). Geographic influences in American history. Ginn and Company.
Lua i Stíl Chicago (17ú heag.)Brigham, Albert Perry. Geographic Influences in American History. Boston: Ginn and Company, 1903.
Lua MLA (9ú heag.)Brigham, Albert Perry. Geographic Influences in American History. Ginn and Company, 1903.
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