@phdthesis{Hildebrandt2013,
author = {Hildebrandt, Klaus},
year = {2013},
title = {Discretization and approximation of the shape operator, the Laplace-Beltrami
operator, and the Willmore energy of surfaces},
type = {Dissertation},
url = "http://dx.doi.org/10.17169/refubium-14902",
}