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^"Great Falls of the Missouri River." Encyclopedia Americana. New York: Americana Corp., 1954.
^Pritchett, Michael. The Melancholy Fate of Capt. Lewis. Columbia, Mo.: Unbridled Books, 2007. ISBN1-932961-41-0
^Shearer, Barbara Smith. State Names, Seals, Flags, and Symbols: A Historical Guide. 3rd rev. ed. Santa Barbara, Calif.: Greenwood Publishing Group, 2002. ISBN0-313-31534-5