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@article{IVM_1979_12_a11, author = {P. A. Ibetov}, title = {Gevrey operator classes with respect to a~hypoelliptic operator}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {67--69}, publisher = {mathdoc}, number = {12}, year = {1979}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1979_12_a11/} }
P. A. Ibetov. Gevrey operator classes with respect to a~hypoelliptic operator. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 12 (1979), pp. 67-69. http://geodesic.mathdoc.fr/item/IVM_1979_12_a11/