@INPROCEEDINGS{Ritschel06,
	author = {Ritschel, T. and Grosch, T.},
	title = {On-line Estimation of Diffuse Materials},
	booktitle = {Dritter Workshop Virtuelle und Erweiterte Realitaet der GI-Fachgruppe VR/AR},
	volume = 3, pages = {95-106},
	year = 2006 }