@article{ZVMMF_1987_27_11_a11,
     author = {S. V. Kurochkin},
     title = {Some estimates for the eigenvalues of a perturbation operator},
     journal = {\v{Z}urnal vy\v{c}islitelʹnoj matematiki i matemati\v{c}eskoj fiziki},
     pages = {1736--1739},
     publisher = {mathdoc},
     volume = {27},
     number = {11},
     year = {1987},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZVMMF_1987_27_11_a11/}
}