@article{Xu:2015:NMD, author = {Hongyi Xu and Funshing Sin and Yufeng Zhu and Jernej Barbi\v{c}}, journal = {ACM Trans. on Graphics (SIGGRAPH 2015)}, number = {4}, title = {Nonlinear Material Design Using Principal Stretches}, volume = {34}, year = {2015} }