Mapping Decline: St. Louis and the Fate of the American City ( <a href="http://mappingdecline.lib.uiowa.edu">http://mappingdecline.lib.uiowa.edu</a> ) represents University of Iowa History Professor Colin Gordon???s examination of how white flight, discriminatory zoning laws, and other factors resulted in the residential segregation that led to the decline of St. Louis???s urban core.