Certain classes of extension of a lacunary Hermitian operator
Certain classes of extensions of a lacunary Hermitian operator are described in terms of abstract boundary conditions. The connection between the asymptotic behavior of eigenvalues of an extension near the boundary of lacuna and the asymptotic of the negative spectrum of the corresponding boundary operator is found.
English version (Springer): Ukrainian Mathematical Journal 44 (1992), no. 2, pp 190-204.
Citation Example: Malamud M. M. Certain classes of extension of a lacunary Hermitian operator // Ukr. Mat. Zh. - 1992. - 44, № 2. - pp. 215-232.