@article{MZM_1973_13_1_a16,
     author = {L. B. Zelenko},
     title = {The limiting spectrum of a~non-self-conjugate second-order differential operator with slowly varying coefficients},
     journal = {Matemati\v{c}eskie zametki},
     pages = {135--146},
     publisher = {mathdoc},
     volume = {13},
     number = {1},
     year = {1973},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1973_13_1_a16/}
}