@inproceedings{shi-min2001modifying,
title={Modifying the shape of NURBS surfaces with geometric constraints},
author={Shi-Min Hu, Youfu Li, Tao JU, and Xiang Zhu},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20160826222652664235461},
booktitle={Computer Aided Design},
volume={33},
number={12},
pages={903-912},
year={2001},
}
Shi-Min Hu, Youfu Li, Tao JU, and Xiang Zhu. Modifying the shape of NURBS surfaces with geometric constraints. 2001. Vol. 33. In Computer Aided Design. pp.903-912. http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20160826222652664235461.