@inproceedings{fan1994a,
title={A Harnack inequality for homogeneous graphs and subgraphs},
author={Fan RK Chung, and Shing-Tung Yau},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20191224203917371774103},
booktitle={Comm. Anal. Geom},
volume={2},
number={4},
pages={627-640},
year={1994},
}

Fan RK Chung, and Shing-Tung Yau. A Harnack inequality for homogeneous graphs and subgraphs. 1994. Vol. 2. In Comm. Anal. Geom. pp.627-640. http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20191224203917371774103.