@inproceedings{w.1951multidimensional,
title={Multidimensional principal integrals, boundary value problems and integral equations},
author={W. J. Trjitzinsky},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203129487096716},
booktitle={Acta Mathematica},
volume={84},
number={1},
pages={1-128},
year={1951},
}
W. J. Trjitzinsky. Multidimensional principal integrals, boundary value problems and integral equations. 1951. Vol. 84. In Acta Mathematica. pp.1-128. http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203129487096716.