D. Harel and Y. Koren.
  <b>Drawing Graphs with Non-Uniform Vertices</b>.
  Technical report, Weizmann Science Press of Israel, 2000.
  <A HREF="http://vis.cs.brown.edu/docs/pdf/bib/g/Harel-2000-DGN.pdf.html">(pdf)</A>
  <A HREF="http://vis.cs.brown.edu/results/bibtex/Harel-2000-DGN.bib">(bibtex:
  Harel-2000-DGN)</A>.<br />