Markus Hadwiger Christoph Berger Helwig Hauser High-Quality Two-Level Volume Rendering of Segmented Data Sets on Consumer Graphics Hardware. 301-308 2003 conf/visualization/2003 IEEE Visualization db/conf/visualization/visualization2003.html#HadwigerBH03 https://doi.org/10.1109/VISUAL.2003.1250386 https://doi.ieeecomputersociety.org/10.1109/VISUAL.2003.1250386 http://dl.acm.org/citation.cfm?id=1081484