Tom Mertens Jan Kautz Philippe Bekaert Frank Van Reeth Hans-Peter Seidel Efficient Rendering of Local Subsurface Scattering. 41-49 2005 24 Comput. Graph. Forum 1 http://www.eg.org/EG/CGF/volume24/issue1/v24i1pp041-049.pdf db/journals/cgf/cgf24.html#MertensKBRS05