@article{Knodel1967,
author = {Knodel, J. and Van de Walle, E.},
title= {Breast feeding, fertility and infant mortality: An analysis of some early German data},
year = {1967},
doi = {10.2307/2172715},
journal = {Population Studies},
volume = {21},
number = {2},
pages = {109--131},
}