Anderson, W. I. (1998). Iowa's geological past: Three billion years of earth history. University of Iowa Press.
Chicago Style (17th ed.) ZitazioaAnderson, Wayne I. Iowa's Geological Past: Three Billion Years of Earth History. Iowa City: University of Iowa Press, 1998.
MLA (9th ed.) ZitazioaAnderson, Wayne I. Iowa's Geological Past: Three Billion Years of Earth History. University of Iowa Press, 1998.
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