@inproceedings{martin1975eigenfunction,
title={Eigenfunction expansions for the Schrödinger operator},
author={Martin Schechter},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203459426236256},
booktitle={Arkiv for Matematik},
volume={14},
number={1},
pages={277-287},
year={1975},
}