The linear inverse problem for the mixed type equation of the second kind of the second order with nonlocal boundary conditions in three-dimensional space

In the present work the problems of correctness of a linear inverse problem for the mixed type equation of the second kind of the second order in three-dimensional space are considered. For this problem, the theorems on existence and uniqueness of the solution are proved in certain class by «$\varepsilon$-regularization» method, Galerkin's and of successive approximations methods.