@inproceedings{françois1982on,
title={On the local solvability and the local integrability of systems of vector fields},
author={François Treves},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203259634335337},
booktitle={Acta Mathematica},
volume={151},
number={1},
pages={1-48},
year={1982},
}
François Treves. On the local solvability and the local integrability of systems of vector fields. 1982. Vol. 151. In Acta Mathematica. pp.1-48. http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203259634335337.