Chris Johnson.
  <b>Top Scientific Visualization Research Problems</b>.
  <i>IEEE Computer Graphics and Applications</i>, 24(4):13-17,
  July/August 2004.
  <A HREF="http://vis.cs.brown.edu/docs/pdf/bib/g/Johnson-2004-TSV.pdf.html">(pdf)</A>
  <A HREF="http://vis.cs.brown.edu/results/bibtex/Johnson-2004-TSV.bib">(bibtex:
  Johnson-2004-TSV)</A>.<br />