@inproceedings{g.1991singular,
title={Singular integrals associated to the Laplacian on the affine group$ax+b$},
author={G. I. Gaudry, T. Qian, and P. Sjögren},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203538168366582},
booktitle={Arkiv for Matematik},
volume={30},
number={1},
pages={259-281},
year={1991},
}

G. I. Gaudry, T. Qian, and P. Sjögren. Singular integrals associated to the Laplacian on the affine group$ax+b$. 1991. Vol. 30. In Arkiv for Matematik. pp.259-281. http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203538168366582.