@article{Kolk2015,
author = {Kolk, M.},
title= {The causal effect of an additional sibling on completed fertility: An estimation of intergenerational fertility correlations by looking at siblings of twins},
year = {2015},
doi = {10.4054/DemRes.2015.32.51},
volume = {32},
number = {51},
pages = {1409--1420},
}