In this work, the theory of boundary value problems is applied to the problem of decomposition of integral functions of two complex variables of the class [n, σ_D] into quasi-exponential basises (the received result generalizes the result received by G. D. Derevyanchenko and V. A. Kakichev) as well as to the problem of decomposition of functions, holomorphic in logarithmically convex limited full bicircular regions, into quasi-exponential basises.