@article{Thygesen2005,
author = {Thygesen, L. and Knudsen, L. and Keiding, N.},
title= {Modelling regional variation of first-time births in Denmark 1980-1994 by an age-period-cohort model},
year = {2005},
doi = {10.4054/DemRes.2005.13.23},
journal = {Demographic Research},
volume = {13},
number = {23},
pages = {573--596},
}