@inproceedings{bo1968direct,
title={Direct sum decompositions in Grothendieck categories},
author={Bo Stenström},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203440560019096},
booktitle={Arkiv for Matematik},
volume={7},
number={5},
pages={427-432},
year={1968},
}