@article{He:1996:CTS,
  author         = "T. He and L. Hong and A. Varshney and S. Wang",
  title          = "Controlled Topology Simplification",
  journal        = "IEEE Transactions on Visualization and Computer Graphics",
  volume     = "2, No 2",
  month      = "June",
  year           = "1996",
  pages          = "171--184"
}