@article{TMF_1971_9_3_a13,
     author = {V. S. Pekar},
     title = {Perturbation theory for one-dimensional {Schrodinger} equations that can be used in a~region where the wave function is small},
     journal = {Teoreti\v{c}eska\^a i matemati\v{c}eska\^a fizika},
     pages = {440--444},
     publisher = {mathdoc},
     volume = {9},
     number = {3},
     year = {1971},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TMF_1971_9_3_a13/}
}