@article{Rosenzweig1980,
author = {Rosenzweig, M. and Wolpin, K.},
title= {Testing the quantity-quality fertility model: The use of twins as a natural experiment},
year = {1980},
doi = {10.2307/1912026},
journal = {Econometrica},
volume = {48},
number = {1},
pages = {227--240},
}