@article{Lesthaeghe2014,
author = {Lesthaeghe, Ron},
title= {The second demographic transition: A concise overview of its development},
year = {2014},
doi = {10.1073/pnas.1420441111},
journal = {Proceedings of the National Academy of Sciences},
volume = {111},
number = {51},
pages = {18112--18115},
}