@inbook{Becker1960,
author = {Becker, G.S.},
title= {An economic analysis of fertility},
year = {1960},
editor = {National Bureau of Economic Research},
booktitle = {Demographic and Economic Change in Developed Countries},
address = {Princeton},
publisher = {Princeton University Press},
pages = {209--231},
series = {NBER Conference Series vol 11},
}