@InProceedings{wald:05:PBRTSketch,
	title	= { {Interactive} {Ray} {Tracing} {of} {Point} {Based} {Models}},
	author	= { Ingo Wald and Hans-Peter Seidel },
	year	= { 2005 },
	booktitle	= { {ACM} {SIGGRAPH} {2005:} {Sketches} {and} {Applications} }
}