@inproceedings{liping2014a,
title={A generalized Koszul theory and its application},
author={Liping Li},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170222103130811898488},
booktitle={Trans. Amer. Math. Soc.},
volume={366},
pages={931-977},
year={2014},
}