@inproceedings{helge1903sur,
title={Sur le prolongement analytique d’une série de Taylor},
author={Helge von Koch},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203012211210117},
booktitle={Acta Mathematica},
volume={27},
number={1},
pages={79-104},
year={1903},
}