Vikas Singh and Deborah Silver.
  <b>Interactive Volume Manipulation with Selective Rendering for
  Improved Visualization</b>.
  <i>IEEE Visualization</i>, 2004.
  <A HREF="http://vis.cs.brown.edu/docs/pdf/bib/g/Singh-2004-IVM.pdf.html">(pdf)</A>
  <A HREF="http://vis.cs.brown.edu/results/bibtex/Singh-2004-IVM.bib">(bibtex:
  Singh-2004-IVM)</A>.<br />