CLASSES OF FUNCTIONS QUASIANALYTIC WITH RESPECT TO A LINEAR HYPERBOLIC OPERATOR OF SECOND ORDER
V G Hryptun · Mathematics of the USSR-Izvestiya · 1970
In analogy with classes of functions which are quasianalytic in the sense of Hadamard, we construct classes of functions which are quasianalytic with respect to operators of the indicated type, acting on two independent variables. We prove a criterion for quasianalyticity.