@article{Van de Kaa2004,
author = {Van de Kaa, D.J.},
title= {Is the second demographic transition a useful research concept? Questions and answers},
year = {2004},
doi = {10.1553/populationyearbook2004s4},
journal = {Vienna Yearbook of Population Research},
volume = {2004},
pages = {4--10},
}