BibTeX Entry: An Improved Physically-Based Soft Shadow Volume Algorithm

@article{Lehtinen2006eurographics,
  author =    {Jaakko Lehtinen and Samuli Laine and Timo Aila},
  title =     {An Improved Physically-Based Soft Shadow Volume Algorithm},
  journal =   {Computer Graphics Forum},
  volume =    {25},
  number =    {3},
  year =      {2006},
  pages =     {303--312},
  publisher = {Eurographics Association and Blackwell Publishing Ltd},
}