Gordon Kindlmann and Ross Whitaker and Tolga Tasdizen and Torsten Moller.
Curvature-Based Transfer Functions for Direct Volume Rendering: Methods and Applications.
In Proceedings of the 14th IEEE Visualization 2003 (VIS'03), pp. 67--74, 2003.

Bibtex:

@InProceedings{ kindlmann:2003:CBTF,
  author =      "Gordon Kindlmann and Ross Whitaker and Tolga Tasdizen
                 and Torsten Moller",
  title =       "Curvature-Based Transfer Functions for Direct Volume
                 Rendering: Methods and Applications",
  booktitle = 	"Proceedings of the 14th IEEE Visualization 2003
                 (VIS'03)",
  pages = 	"67--74",
  year = 	"2003",
}

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