@article{Liu2020,
author = {Liu, H. and Umberson, D. and Xu, M.},
title= {Widowhood and mortality: Gender, race/ethnicity, and the role of economic resources},
year = {2020},
doi = {10.1016/j.annepidem.2020.02.006},
volume = {45},
pages = {69--75},
}