Naoki Katoh, Takeshi Tokuyama. K-Levels of Concave Surfaces. Discrete & Computational Geometry, 27(4):567-584, 2002. [doi]
@article{KatohT02,
title = {K-Levels of Concave Surfaces},
author = {Naoki Katoh and Takeshi Tokuyama},
year = {2002},
url = {http://link.springer.de/link/service/journals/00454/contents/01/0086/index.html},
researchr = {https://researchr.org/publication/KatohT02},
cites = {0},
citedby = {0},
journal = {Discrete & Computational Geometry},
volume = {27},
number = {4},
pages = {567-584},
}