Urbanization and productivity : evidence from Turkish provinces over the period 1980 - 2000 / Souleymane Coulibaly; Uwe Deichmann; Somik Lall. Washington, DC : World Bank, Sustainable Development Network, Urban Unit, Aug. 2007 ; Halle (Saale) : Universitäts- und Landesbibliothek Sachsen-Anhalt, Aug. 2007