@inproceedings{l.1958the,
title={The critical lattices of a star-shaped octagon},
author={L. E. Clarke},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203149768543870},
booktitle={Acta Mathematica},
volume={99},
number={1},
pages={1-32},
year={1958},
}