@article{li2007curve,
  title={Curve space: Classifying curves on surfaces},
  author={Li, Xin and Gu, Xianfeng and Qin, Hong and others},
  journal={Communications in Information \& Systems},
  volume={7},
  number={3},
  pages={207--226},
  year={2007},
  publisher={International Press of Boston}
}