@inproceedings{nan2012bounding,
title={BOUNDING GEOMETRY OF LOOPS IN ALEXANDROV SPACES},
author={Nan Li, and Xiaochun Rong},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20160913231219208913941},
booktitle={Journal of Differential Geometry},
volume={92},
number={1},
pages={31-54},
year={2012},
}

Nan Li, and Xiaochun Rong. BOUNDING GEOMETRY OF LOOPS IN ALEXANDROV SPACES. 2012. Vol. 92. In Journal of Differential Geometry. pp.31-54. http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20160913231219208913941.