Jarke J. van Wijk.
  <b>Spot Noise texture Synthesis for Data Visualization</b>.
  In <i>Proceedings of ACM SIGGRAPH 1991</i>, pages 309-318. ACM Press,
  1991.
  <A HREF="http://vis.cs.brown.edu/docs/pdf/bib/g/vanWijk-1991-SNT.pdf.html">(pdf)</A>
  <A HREF="http://vis.cs.brown.edu/results/bibtex/vanWijk-1991-SNT.bib">(bibtex:
  vanWijk-1991-SNT)</A>.<br />