@article{Sun15:TP,
    author = {Timothy Sun and Changxi Zheng},
    title  = {Computational Design of Twisty Joints and Puzzles},
    journal = {ACM Transactions on Graphics (Proceedings of SIGGRAPH 2015)},
    year = {2015},
    volume = {34},
    number = {4},
    month  = Aug,
    url = {http://www.cs.columbia.edu/cg/twisty}
}