Weyl function for sum of operators tensor products

The boundary triplets approach is applied to the construction of self-adjoint extensions of the operator having the form S = A ⊗ I T + I A ⊗ T where the operator A is symmetric and the operator T is bounded and self-adjoint. The formula for the γ-field and the Weyl function corresponding the the boundary triplet Π S is obtained in terms of the γ-field and the Weyl function corresponding to the boundary triplet Π A.