@inproceedings{lai2020on,
title={On the number of edges in some graphs},
author={Lai Chunhui},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20190512095121802105344},
booktitle={Discrete Applied Mathematics (2020), https://doi.org/10.1016/j.dam.2020.03.008 },
volume={283},
pages={751–755},
year={2020},
}

Lai Chunhui. On the number of edges in some graphs. 2020. Vol. 283. In Discrete Applied Mathematics (2020), https://doi.org/10.1016/j.dam.2020.03.008 . pp.751–755. http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20190512095121802105344.