4Duranton G. , Puga D.. Diversity and Specialization in Cities: Why, Where and When Does It Matter [J]. Urban Studies, 2000, 37 (3): 533-55.
5Rosenthal S. , Strange W.. Evidence on the Nature and Sources of Agglomeration Economies [J] Handbook o4 Regional and Urban Economics, 2004, Amsterdam: North Holland, 2119-2171.
6Brulhart M., Sbergami F.. Agglomeration and Growth: Cross-country Evidence [J]. Journal of Urban Economics, 2009, 65 (1): 48-63.
7Krugman P.. Increasing Returns and EconomicGeography [J]. The Journal of Political Economy, 1991, 483-499.
