@article{alss-vdr-03,
  author    = "Pierre Alliez and Nathalie Laurent and Henri Sanson and Francis Schmitt",
  title     = {Efficient View-dependent Refinement of 3D Meshes using
               Sqrt(3)-Subdivision},
  journal   = {the Visual Computer},
  volume = {19(4}},
  month = {july},
pages = {205-221},
  year      = "2003"}