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.
@article{119418,
author = {Genadij O. Hakobyan and V. N. Margaryan},
title = {Gevrey hypoellipticity for a class of degenerated quasi-elliptic operators},
journal = {Commentationes Mathematicae Universitatis Carolinae},
volume = {44},
year = {2003},
pages = {637-644},
zbl = {1098.35058},
mrnumber = {2062880},
language = {en},
url = {http://dml.mathdoc.fr/item/119418}
}
Hakobyan, Genadij O.; Margaryan, V. N. Gevrey hypoellipticity for a class of degenerated quasi-elliptic operators. Commentationes Mathematicae Universitatis Carolinae, Tome 44 (2003) pp. 637-644. http://gdmltest.u-ga.fr/item/119418/
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