1. Mathematical Methods for Physicists;Arfken,1970
2. Agglomeration and endogenous capital;Baldwin;European Economic Review,1999
3. New ways of looking at cities;Batty;Nature,1995
4. Chincarini, L., 1995. The dynamics of city formation. Ph.D. Dissertation, Chapter 1, Massachusetts Institute of Technology, Department of Economics.
5. Die Zentralen Orte in Suddeutschland;Christaller,1933