@inproceedings{r.1887beweis,
title={Beweis Eines Satzes},
author={R. Lipschitz},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108202941793350852},
booktitle={Acta Mathematica},
volume={10},
number={1},
pages={137-144},
year={1887},
}