@inproceedings{c.1973on,
title={On absolutely convergent Fourier series},
author={C. W. Onneweer},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203452856189199},
booktitle={Arkiv for Matematik},
volume={12},
number={1},
pages={51-58},
year={1973},
}