@article{Ramamoorthi:2001:RRI,
  year = 2001,
  journal = {Journal of the Optical Society of America (JOSA)},
  title = {On the relationship between Radiance and Irradiance: Determining the illumination from images of a convex Lambertian object},
  author = {Ramamoorthi, Ravi and Hanrahan, Pat},
  url = {http://graphics.cs.berkeley.edu/papers/Ramamoorthi-RRI-2001-00/},
}