Ward, Barbara
The interply of East and West: points of conflct and operation
Norton & Comp , 1957
 Buku Teks SO
Toynbee, Arnold J.
The world and the west
Oxford University Press, 1957
 Buku Teks SO
Carpenter, Allan
The encyclopedia of the central west
Facts On File, 1990
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Encyclopedia of the American west
editors Charles Phillips, Alan Axelrod
Simon & Schuster Macmillan, 1996
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Cohen, Edi
West coast rooms
Rockport Publishers, 2000
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