@article{Abma2006,
author = {Abma, J.C. and Martinez, G.M.},
title= {Childlessness Among Older Women in the United States: Trends and Profiles},
year = {2006},
doi = {10.1111/j.1741-3737.2006.00312.x},
journal = {Journal of Marriage and Family},
volume = {68},
number = {4},
pages = {1045--1056},
}