@Article{SCI:Bre2004a,
  author =    "P.-T. Bremer and H. Edelsbrunner and B. Hamann and
              V. Pascucci",
  title =     "A Topological Hierarchy for Functions on
              Triangulated Surfaces",
  journal =   "IEEE Transactions on Visualization and Computer
              Graphics",
  volume =    "10",
  number =    "4",
  pages =     "385-396",
  year =      "2004",
  month =     "July/August",
  note =      "UCRL-JRNL-208700",
}