@article{Green:2007:ERV,
  author = "Paul Green and Jan Kautz and Fr\'edo Durand",
  title  = "Efficient Reflectance and Visibility Approximations for Environment Map Rendering",
  journal= "Computer Graphics Forum (Proc. EUROGRAPHICS)",
  year   = 2007,
  volume = 26,
  number = 3,
  pages  = "495--502",
}