@inproceedings{jianqing2008semiparametric,
title={Semiparametric estimation of covariance matrixes for longitudinal data},
author={Jianqing Fan, and Yichao Wu},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20191221113633587732871},
booktitle={Journal of the American Statistical Association},
volume={103},
number={484},
pages={1520-1533},
year={2008},
}
Jianqing Fan, and Yichao Wu. Semiparametric estimation of covariance matrixes for longitudinal data. 2008. Vol. 103. In Journal of the American Statistical Association. pp.1520-1533. http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20191221113633587732871.