@Article{SCI:Tri2003a,
  author =    "X. Tricoche and G. Scheuermann",
  title =     "Topology Simplification of Symmetric, Second Order
              2D Tensor Fields",
  journal =   "Geometric Modeling Methods in Scientific
              Visualization",
  pages =     "171--184",
  year =      "2003",
  publisher = "Springer, Berlin",
  url =       "http://www.sci.utah.edu/publications/tricoche03/simple.pdf",
}