@inproceedings{n.1962a,
title={A unique continuation theorem for exterior differential forms on Riemannian manifolds},
author={N. Aronszajn, A. Krzywicki, and J. Szarski},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203427740809988},
booktitle={Arkiv for Matematik},
volume={4},
number={5},
pages={417-453},
year={1962},
}
N. Aronszajn, A. Krzywicki, and J. Szarski. A unique continuation theorem for exterior differential forms on Riemannian manifolds. 1962. Vol. 4. In Arkiv for Matematik. pp.417-453. http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203427740809988.