@article{kir-02-opg,
  author = {Kevin G. Kirby},
  title = {Beyond the Celestial Sphere: {Oriented} Projective Geometry and Computer Graphics},
  journal = {Mathematics Magazine},
  volume = {75},
  number = {5},
  pages = {351--366},
  year = 2002,
  month = dec,
  url = {http://links.jstor.org/sici?sici = 0025-570X\%28200212\%2975\%3A5\%3C351\%3ABTCSOP\%3E2.0.CO\%3B2-6},
  abstract = {Software for computer graphics represents three-dimensional space a little differently than one might expect. Euclidean geometry is not quite right. The usual approach uses what is called \emph{projective geometry}, certainly one of the most beautiful systems in mathematics. Yet even with this approach, when the mathematics actually meets computer code there are some awkward inconveniences. Perhaps the best solution may be what is called \emph{oriented projective geometry}. This geometry was worked out in detail by Jorge Stolfi~[sto-87-opg,sto-91-opg] in 1987; it has also found more recent application in computer vision~[lav-fau-96-orivis]. [\dots]}
}