the greatest development of the theory of migration falls in the 1970s and 1980s (theories at the micro level); see, among others: 1) L.A. Sjaastad, The Costs and Returns of Human Migration, Journal of Political Economy, vol. 70 5/1962 the Sjaastad model was developed by Harris and Todaro: 2 MP. Todaro, the model of labor migration and urban unemployment in less developed countries, American Economic Review 5 (1) / 1969; J.R. Harris, M.P. Todaro, migration, unemployment and development: Analysis of two sectors, The American Economic Review 60 (1) / 1970 In 1966, E.S. Lee proposed a push and pull theory: 3) E.S. Lee, Theory of migration and in the 1980s, the New Economics of Economic Migration emerged, initiated by the work of O. Stark (and later O. Stark, D.E. Bloom, R.E.B. Lucas and S. Yitzhaki): 4) O.Stark, D.E. Bloom, New economics of labor migration, The American Economic Review 75 (2) / 1985, 5) O. Stark, S. Yitzhaki, labor migration as a response to a relative lack, Journal of Population Economics 1 (1) / 1988 6) O. Stark, R.E.B. Lucas, migration, remittances and family, economic development and cultural changes, Vol. 36 (3) / 1988 I can suggest a study that excellently synthesizes above theories:
7) D.S. Massey, Why is immigration? Theoretical synthesis, [in:] The Handbook of International Migration: The American Experience, Eds. Ch. Hirschman, P. Kasinitz, J. Dewind, Russell Sage Foundation, 1999
As part of contemporary works, I recommend you the works of prof. M. Okólski, who significantly contributes to the development of the concept of migration in the context of transition.
Thank you so much..I am not researching this area, butbit came as an idea through our research results..now I am fighting with something new.. I have the Massey paper.
One of the most important factors determining the future of international migration of the population will be climate change and economic and political processes occurring in individual regions of the world, in individual countries.