@article{Yi2004,
author = {Yi, Zeng and Vaupelly, James W.},
title= {Association of late childbearing with healthy longevity among the oldest-old in China},
year = {2004},
doi = {10.1080/0032472032000175437},
journal = {Population Studies},
volume = {58},
number = {1},
pages = {37--53},
}