@article{MZM_1982_31_5_a7,
     author = {A. I. Karol' and M. Z. Solomyak},
     title = {Class of differential operators with abnormal behavior of the spectrum of the {Dirichlet} problem},
     journal = {Matemati\v{c}eskie zametki},
     pages = {747--751},
     publisher = {mathdoc},
     volume = {31},
     number = {5},
     year = {1982},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1982_31_5_a7/}
}