@inproceedings{f.1903über,
title={Über die Moduln der Thetafunctionen},
author={F. Schottky},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203013456685129},
booktitle={Acta Mathematica},
volume={27},
number={1},
pages={235-288},
year={1903},
}