7E, Chamberlin, The Theory of Monopolistic Competition, Cambridge: Harvard University Press·1933.
8P. Krugman, "Increasing Returns and Economic Geography, ” Journal of Political Economy,Vol. 99,No. 3(1991),pp. 483 - 499.
9M Fujita,P. Krugman & T. Mori, "On the Evolution of Hierarchical Urban Systems, ( European EconomicRexneu), Vol. 43,No. 2(1999),pp. 209 - 251.
10H. Takatsuka & D. Z. Zeng,"Dispe rsion Forms: An Interaction of Market Access, Competition, and UrbanCosts, " Journal of Regional Science 49, No. 1(2009) , pp. 177 - 204.