@INPROCEEDINGS{ZMHH97,
  AUTHOR = "H. Zhang and D. Manocha and T. Hudson and K. Hoff",
  TITLE = "Visibility Culling using Hierarchical Occlusion Maps",
  BOOKTITLE = SIGGRAPH,
  YEAR = 1997
}

@ARTICLE{TS91,
  AUTHOR = "S. Teller and C. S\'{e}quin",
  TITLE = "Visibility Preprocessing for interactive walkthroughs",
  VOLUME = 25,
  NUMBER = 4,
  JOURNAL = "Computer Graphics",
  PAGES = "61--69",
  YEAR ="1991"}

@inproceedings{ct97,
  AUTHOR =      "S. Coorg and S. Teller",
  TITLE =       "Real-Time Occlusion Culling for Models with Large Occluders",
  BOOKTITLE =   ACM SIGGRAPH Symposium in Interactive 3D Graphics",
  PAGES =       "83--90",
  YEAR =        1997
}

@INPROCEEDINGS{GKM93,
  AUTHOR = "N. Greene and M. Kass and G. Miller",
  TITLE = "Hierarchical Z-Buffer Visibility",
  BOOKTITLE = SIGGRAPH,
  PAGES = "231--238",
  YEAR ="1993"}

@INPROCEEDINGS{KM96v,
    AUTHOR = "S. Kumar and D. Manocha",
    TITLE = "Hierarchical Visibility Culling for Spline Models",
    BOOKTITLE = "Graphics Interface",
    ADDRESS = "Toronto, Canada",
    PAGES = "142--150",
    YEAR = 1996}

@INPROCEEDINGS{KMGL96,
  AUTHOR = "S. Kumar and D. Manocha and B. Garrett and M. Lin",
  TITLE = "Hierarchical Back-Face Culling",
  BOOKTITLE = "7th Eurographics Workshop on Rendering",
  ADDRESS = "Porto, Portugal",
  PAGES = "231--240",
  YEAR = 1996}