@inproceedings{claus2018the,
title={The quantization of gravity},
author={Claus Gerhardt},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20160919235428971331020},
booktitle={Adv. Theor. Math. Phys.},
volume={22},
number={3},
pages={709 - 757},
year={2018},
}

Claus Gerhardt. The quantization of gravity. 2018. Vol. 22. In Adv. Theor. Math. Phys.. pp.709 - 757. http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20160919235428971331020.