@inproceedings{yong2013nodal,
title={Nodal geometry of graphs on surfaces},
author={Yong Lin, Gbor Lippner, Dan Mangoubi, and Shing-Tung Yau},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20191224204711554393209},
booktitle={arXiv preprint arXiv:1307.3226},
year={2013},
}