@inproceedings{j.1951the,
title={The problem of unitary equivalence},
author={J. Brenner},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203132883481744},
booktitle={Acta Mathematica},
volume={86},
number={1},
pages={297-308},
year={1951},
}