1. Archer, J. Clark. “Occupational Segregation in Urban Residential Space.” Ph.D. Thesis University of Iowa, May, 1974.
2. Banfield, Edward C., and Wilson, James Q.City Politics. New York: Random House, 1963.
3. Bish, Robert L.The Public Economy of Metropolitan Areas. Chicago: Markham, 1971.
4. Buchanan, James M., and Tullock, Gordon.The Calculus of Consent. Ann Arbor: University of Michigan Press, 1962.
5. Cox, Kevin R. “The Voting Decision in a Spatial Context.”Progress in Geography I. Edited by C. Board, R. J. Chorley, P. Haggett, and D. Stoddart. London: Edward Arnold, 1969.