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2. Product differentiation, monopolistic competition and city size
3. Agglomeration economies, types, and sizes of cities
4. PRODUCT VARIETY, MARSHALLIAN EXTERNALITIES, AND CITY SIZES*
5. Hesham M. Abdel-Rahman, and J. Vernon Henderson, 1988 . "Efficiency through Decentralization with Product Diversity," Working Paper No. 88-22, Department of Economics, Brown University.