@article{Keyfitz1980,
author = {Keyfitz, N.},
title= {Do cities grow by natural increase or by migration?},
year = {1980},
doi = {10.1111/j.1538-4632.1980.tb00024.x},
URL = {https://doi.org/10.1111/j.1538-4632.1980.tb00024.x},
volume = {12},
number = {2},
pages = {142--156},
}