%0 Journal Article %A T. H. Rasulov %A E. B. Dilmurodov %T Analysis of the spectrum of a $2\times 2$ operator matrix. Discrete spectrum asymptotics %J Nanosistemy: fizika, himiâ, matematika %D 2020 %P 138-144 %V 11 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/item/NANO_2020_11_2_a1/ %G en %F NANO_2020_11_2_a1