6Griffith D A. Urban Dominance, Spatial Structure and Spatial Dynamics: Some Theoretical Conjectures and Empirical Implications, Economic Geogrephy, May. 1979.
7Friedmann J. The Spatial Organization of Power in the Development of Urban Systems, Comparative Urban Research, Janurary. 1972.
8Martin, Ron Peter Sunley. Slow Convergence? The New Endogenous Growth Theory and Regional Development. Economic Geography . March. 1998.
9Quispel A. Some Theoretical Aspects of Symbiosis. Antonie Van Leeuwenhoek, Janurary. 1951.
10Ahmadjian, V. and S. Paracer. Symbiosis : an Introduction to Biological Association. Hanover & London: University Press of New England. 1986.
