U. M. Norberg and J. M. V. Rayner.
  <b>Ecological Morphology and Flight in Bats. Wing Adaptations,
  Flight Performance, Foraging Strategy and Echolocation</b>.
  <i>Philosophical Transactions of the Royal Society of London Series
  B-Biological Sciences</i>, 316:337-419, 1987.
  <A HREF="http://vis.cs.brown.edu/docs/pdf/bib/g/Norberg-1987-EMF.pdf.html">(pdf)</A>
  <A HREF="http://vis.cs.brown.edu/results/bibtex/Norberg-1987-EMF.bib">(bibtex:
  Norberg-1987-EMF)</A>.<br />