Andrew Witkin and Michael Kass.
  <b>Reaction-diffusion textures</b>.
  In <i>Proceedings of the 18th annual conference on Computer
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  <A HREF="http://vis.cs.brown.edu/results/bibtex/Witkin-1991-RDT.bib">(bibtex:
  Witkin-1991-RDT)</A>.<br />