Article
Keywords:
Gevrey class; Gevrey hypoellipticity; hypoelliptic operator; degenerated \newline quasi-elliptic operator
Summary:
The problems of Gevrey hypoellipticity for a class of degenerated quasi-elliptic operators are studied by several authors (see [1]--[5]). In this paper we obtain the Gevrey hypoellipticity for a degenerated quasi-elliptic operator in $\Bbb R^2$, without any restriction on the characteristic polyhedron.
References:
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