Wong, S., Colarco, P.R., Dessler, and A.E.
  <b>Principal component analysis of the evolution of the Saharan
  air layer and dust transport: Comparisons between a model simulation and
  MODIS and AIRS retrievals</b>.
  <i>J. Geophys. Res.</i>, 2006.
  <A HREF="http://vis.cs.brown.edu/docs/pdf/bib/g/WONG-2006-PCA.pdf.html">(pdf)</A>
  <A HREF="http://vis.cs.brown.edu/results/bibtex/WONG-2006-PCA.bib">(bibtex:
  WONG-2006-PCA)</A>.<br />