@inbook{Cassell2002,
author = {Cassell, P.-G. },
title= {Changing seasonality of births in Sweden 1900-1999},
year = {2002},
editor = {Carling, J.},
booktitle = {Nordic Demography: Trends and Differentials. Scandinavian Population Studies},
address = {Oslo},
publisher = {Unipub forlag/Nordic Demographic Society},
pages = {97--110},
}