@article{IIMI_2006_1_a6,
     author = {M. S. Smetanina},
     title = {Levels of the {Schr\"odinger} operator with a perturbed non-local potential},
     journal = {Izvestiya Instituta Matematiki i Informatiki Udmurtskogo Gosudarstvennogo Universiteta},
     pages = {98--104},
     year = {2006},
     number = {1},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IIMI_2006_1_a6/}
}