Daniel Keefe and David H. Laidlaw.
  <b>Analysis of Performance in Precise 3D Curve Input Tasks in
  Virtual Reality</b>.
  IEEE Visualization 2007 Poster, 2007.
  <A HREF="http://vis.cs.brown.edu/docs/pdf/g/Keefe-2007-APP.pdf.html">(pdf)</A>
  <A HREF="http://vis.cs.brown.edu/results/bibtex/Keefe-2007-APP.bib">(bibtex:
  Keefe-2007-APP)</A>.<br />