@article{Frejka2007,
author = {Frejka, T.  and Sardon, J.P.},
title= {Cohort birth order, parity progression ratio and parity distribution trends in developed countries},
year = {2007},
doi = {10.4054/DemRes.2007.16.11},
journal = {Demographic Research},
volume = {16},
number = {11},
pages = {315--374},
}