Much of the information contained in this exhibit came from the following source:
Archer, J. Clark, Stephen J. Lavin, Kenneth C. Martis and Fred M. Shelley. Historical Atlas of U.S. Presidential Elections, 1788-2004. CQ Press (Washington, DC), 2006. (Find this item in the Duke Library Catalog)
More information about U.S. presidents and presidential elections can be found in these locations: