@Article{SCI:Sch2013a,
  author =    "M. Schott and T. Martin and A.V.P. Grosset and
              S.T. Smith and C.D. Hansen",
  title =     "Ambient Occlusion Effects for Combined Volumes and
              Tubular Geometry",
  journal =   "IEEE Transactions on Visualization and Computer
              Graphics (TVCG)",
  volume =    "19",
  number =    "6",
  pages =     "913--926",
  year =      "2013",
  note =      "Selected as Spotlight paper for June 2013 issue",
  doi =       "10.1109/TVCG.2012.306",
  keywords =  "Volume rendering, ambient occlusion, stream
              tubes",
  url =       "http://www.sci.utah.edu/publications/schott13/Schott_TVCG2013.pdf",
}