Chandrajit L. Bajaj and Valerio Pascucci and Daniel R. Schikore.
The Contour Spectrum.
In Proceedings of Visualization '97, pp. 167--173, 1997.

Bibtex:

@InProceedings{  bajaj:1997:TCS,
  author = 	 {Chandrajit L. Bajaj and Valerio Pascucci and Daniel
                  R. Schikore},
  title = 	 {The Contour Spectrum},
  booktitle =    {Proceedings of Visualization '97},
  pages = 	 {167--173},
  year = 	 {1997},
}

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