@inproceedings{yixistudy,
title={Study on the Properties of Circumscribed Ellipses of Convex Quadrilaterals},
author={Yixi Shen},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20160813215158139777162},
}
Yixi Shen. Study on the Properties of Circumscribed Ellipses of Convex Quadrilaterals. http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20160813215158139777162.