@article{Massey1997,
author = {Massey, D.S. and Espinosa, K.E. },
title= {What’s driving Mexico–U.S. migration? A theoretical, empirical, and policy analysis},
year = {1997},
doi = {10.1086/231037},
journal = {American Journal of Sociology },
volume = {102},
number = {4},
pages = {939--999},
}