Susanne Lange.
  <b>A Visualization Support Model</b>.
  Technical Report 97.08, University of Leeds, 1997.
  <A HREF="http://vis.cs.brown.edu/docs/pdf/bib/g/Lange-1997-VSM.pdf.html">(pdf)</A>
  <A HREF="http://vis.cs.brown.edu/results/bibtex/Lange-1997-VSM.bib">(bibtex:
  Lange-1997-VSM)</A>.<br />