MathSciDoc: An Archive for Mathematician ∫

@inproceedings{matts1958on,
  title={On homomorphisms and orthogonal systems},
  author={Matts Essén},
  url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203423254285948},
  booktitle={Arkiv for Matematik},
  volume={3},
  number={6},
  pages={505-514},
  year={1958},
}