Cities, towns, and poverty : migration equilibrium and income distribution in a todaro-type model with multiple destinations / Luc Christiaensen (The World Bank), Joachim De Weerdt (University of Antwerp and KU Leuven), Ravi Kanbur (Cornell University and IZA) ; IZA, Institute of Labor Economics. Bonn, Germany : IZA Institute of Labor Economics, April 2017