@ARTICLE{gassenbauer09spatial,
  author  = {V\'aclav Gassenbauer and Jaroslav K\v{r}iv\'anek and Kadi Bouatouch},
  title   = {Spatial Directional Radiance Caching},
  journal = {Computer Graphics Forum (Proc. of Eurographics Symposium on Rendering)},
  year    = {2009},
  volume  = {28},
  number  = {4},
  pages   = {1189--1198},
}