1. Spectral Theory of Self-Adjoint Operators in Hilbert Space;Birman,1987
2. Boundary triplets, tensor products and point contacts to reservoirs;Boitsev;Ann. Henri Poincaré,2018
3. Weyl function for sum of operators tensor products;Boitsev;Nanosyst., Phys. Chem. Math.,2013
4. Boundary triplets and Weyl functions. Recent developments;Derkach,2012
5. Generalized resolvents and the boundary value problems for Hermitian operators with gaps;Derkach;J. Funct. Anal.,1991