ON SMOOTHNESS OF THE SOLUTION TO A NONLOCAL BOUNDARY VALUE PROBLEM OF PERIODIC TYPE FOR A FOURTH-ORDER MIXED-TYPE EQUATION OF THE SECOND KIND
In this paper, using the modified Galerkin method and the methods of a priori
estimates, “"-regularization”, we study the unique solvability and smoothness of a
regular generalized solution of a nonlocal boundary value problem of periodic type
for a mixed type equation of the second kind of the fourth order in Sobolev spaces
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