@inproceedings{pavel2007on,
title={On the critical exponent in an isoperimetric inequality for chords},
author={Pavel Exner, Martin Fraas, and Evans M Harrell II},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20191020133149671879731},
booktitle={Physics Letters A},
volume={368},
pages={1-6},
year={2007},
}

Pavel Exner, Martin Fraas, and Evans M Harrell II. On the critical exponent in an isoperimetric inequality for chords. 2007. Vol. 368. In Physics Letters A. pp.1-6. http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20191020133149671879731.