@article{DBLP:journals/tog/RayVLL08,
  author    = {Nicolas Ray and
               Bruno Vallet and
               Wan-Chiu Li and
               Bruno L{\'e}vy},
  title     = {N-symmetry direction field design},
  journal   = {ACM Trans. Graph.},
  volume    = {27},
  number    = {2},
  year      = {2008},
  ee        = {http://doi.acm.org/10.1145/1356682.1356683},
  bibsource = {DBLP, http://dblp.uni-trier.de}
}