@article{Lehtinen2008Hierarchical,
author = {Jaakko Lehtinen and Matthias Zwicker and Emmanuel Turquin and Janne Kontkanen and Fr\'{e}do Durand and Fran\c{c}ois Sillion and Timo Aila},
title = {A Meshless Hierarchical Representation for Light Transport},
journal = {ACM Trans. Graph.},
volume = 27,
number = 3,
OPTpages = {},
year = {2008},
}