1. Rotter, I.: A non-Hermitian Hamilton operator and the physics of open quantum systems. J. Phys. A: Math. Theor. 42(No15), 153001 (2009). https://doi.org/10.1088/1751-8113/42/15/153001
2. Muminov, M.I., Rasulov, T.H.: Embedded eigenvalues of a Hamiltonian in bosonic fock space. Commun. Math. Anal. 17(1), 1–22 (2014)
3. Golub, G.H., Van Loon, C.F.: Matrix Computations. The Johns Hopkins University Press, Baltimore (1996)
4. Isaacson, E., Keller, H.B.: Analysis of Numerical Methods. Dover Publications, Mineola; Wiley, New York (1996). ISBN 0-486-68029-0
5. LNCS;V Alexandrov,2015