@article{Kohler2002, author = {Kohler, Hans-Peter and Billari, Francesco C. and Ortega, José Antonio}, title= {The Emergence of Lowest-Low Fertility in Europe During the 1990s}, year = {2002}, doi = {10.1111/j.1728-4457.2002.00641.x}, journal = {Population and Development Review}, volume = {28}, number = {4}, pages = {641--680}, }