@article{Xue1996,
author = {Xue, X. and Brookmeyer, R.},
title= {Bivariate frailty model for the analysis of multivariate survival time},
year = {1996},
doi = {10.1007/bf00128978},
journal = {Lifetime Data Analysis},
volume = {2},
number = {3},
pages = {277--289},
}