The smoothness of $\operatorname{CR}$-mappings between strictly pseudoconvex hypersurfaces

In this article it is proved that if $\Gamma_1$, and $\Gamma_2$ are strictly pseudoconvex hypersurfaces in $\mathbf C^n$ of class $C^m$ for ($m>2$) and if $F\colon\Gamma_1\to\Gamma_2$ is a continuous nonconstant $\operatorname{CR}$-mapping, then $F$ is a local diffeomorphism of class $C^{m-1-0}$.
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