@article{DAN_1988_300_4_a2,
     author = {V. D. Koshmanenko},
     title = {Uniqueness of a singularly perturbed operator},
     journal = {Doklady Akademii Nauk},
     pages = {786--789},
     publisher = {mathdoc},
     volume = {300},
     number = {4},
     year = {1988},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1988_300_4_a2/}
}