@article{DAN_1987_293_5_a8,
     author = {V. A. Sadovnichii and V. A. Lyubishkin and M. Martinovi\v{c}},
     title = {Finite-dimensional perturbations of discrete operators, and trace formulas},
     journal = {Doklady Akademii Nauk},
     pages = {1062--1064},
     publisher = {mathdoc},
     volume = {293},
     number = {5},
     year = {1987},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1987_293_5_a8/}
}