@inproceedings{mu-tao2014minkowski,
title={Minkowski formulae and Alexandrov theorems in spacetime},
author={Mu-Tao Wang, Ye-Kai Wang, and Xiangwen Zhang},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20160820133107813504318},
year={2014},
}

Mu-Tao Wang, Ye-Kai Wang, and Xiangwen Zhang. Minkowski formulae and Alexandrov theorems in spacetime. 2014. http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20160820133107813504318.