@article{Plane2005,
author = {Plane, D.A. and Henrie, C.J. and Perry, M.J.},
title= {Spatial demography special feature: migration up and down the urban hierarchy and across the life course},
year = {2005},
doi = {10.1073/pnas.0507312102},
journal = {Proceedings of the National Academy of Sciences},
volume = {102},
pages = {15313--15318},
}