@InProceedings{jue:09m,
author = {M. Aigner and L. Gonzalez-Vega and M. L. Sampoli and B. J\"uttler},
title = {Computing Isophotes on Free-form surfaces based on 
 Support Function Approximation},
booktitle = {The Mathematics of Surfaces XIII},
year =  {2009},
editor =  {E. Hancock and R. Martin},
series =  {Lecture Notes in Computer Science},
publisher = {Springer},
pages = {1--18},
volume = {5654},
}