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By Mark Bjelland, David Kaplan, Jon Malinowski. Mark Bjelland is professor of geography at Calvin UniversityDavid H. Kaplan is a professor of geography at Kent State University. He received his Ph.D. from the University of Wisconsin at Madison and his B.A. from The Johns Hopkins University.
When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.