@article{Hildebrandt2011,
author = "Klaus Hildebrandt and Konrad Polthier",
title = "Generalized shape operators on polyhedral surfaces",
journal = "Computer Aided Geometric Design",
volume = "28",
number = "5",
pages = "321 - 343",
year = "2011",
issn = "0167-8396",
doi = "DOI: 10.1016/j.cagd.2011.05.001",
url = "http://www.sciencedirect.com/science/article/pii/S0167839611000628",

}