@article{Kiernan1983,
author = {Kiernan, K.E. and Diamond, I.},
title= {The age at which childbearing starts — a longitudinal study},
year = {1983},
doi = {10.1080/00324728.1983.10408867},
journal = {Population Studies},
volume = {37},
number = {3},
pages = {363--380},
}