@inproceedings{mu-tao2011gravitational, title={Gravitational energy seen by quasilocal observers}, author={Mu-Tao Wang}, url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20160820183722757136343}, booktitle={Classical and Quantum Gravity}, volume={28}, number={11}, pages={114011}, year={2011}, }