@techreport{Andersson2001,
author = {Andersson, G. and Sobolev, B.},
title= {Small effects of selective migration and selective survival in retrospective studies of fertility},
year = {2001},
URL = {http://www.demogr.mpg.de/Papers/Working/wp-2001-031.pdf},
address = {Rostock},
institution = {MPIDR Working Paper 2001-031, Max Planck Institute for Demographic Research},
}