Diego Gutierrez Francisco J. Serón Jorge Lopez-Moreno Maria P. Sanchez Jorge Fandos Erik Reinhard Depicting procedural caustics in single images. 120 2008 27 ACM Trans. Graph. 5 http://doi.acm.org/10.1145/1457515.1409073 db/journals/tog/tog27.html#GutierrezSLSFR08