@inproceedings{nils1930ivar,
title={Ivar Fredholm},
author={Nils Zeilon},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203053288905443},
booktitle={Acta Mathematica},
volume={54},
number={1},
pages={I-XVI},
year={1930},
}