@article{Frejka2006, author = {Frejka, T. and Sardon, J.-P.}, title= {First birth trends in developed countries. Persisting parenthood postponement}, year = {2006}, doi = {10.4054/DemRes.2006.15.6}, URL = {http://www.demographic-research.org/volumes/vol15/6/}, journal = {Demographic Research}, volume = {15}, number = {6}, pages = {147--180}, }