Martin Wattenberg and Danyel Fisher.
  <b>A Model of Multi-Scale Perceptual Organization in Information
  Graphics</b>.
  In <i>Proceedings of IEEE Symposium on Information Visualization</i>,
  October 2003.
  <A HREF="http://vis.cs.brown.edu/docs/pdf/bib/g/Wattenberg-2003-MMS.pdf.html">(pdf)</A>
  <A HREF="http://vis.cs.brown.edu/results/bibtex/Wattenberg-2003-MMS.bib">(bibtex:
  Wattenberg-2003-MMS)</A>.<br />