@article{DE_1982_18_10_a5,
     author = {Ya. T. Sultanaev},
     title = {Asymptotic behavior of the spectrum of ordinary differential operators in the degenerate case},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1694--1702},
     publisher = {mathdoc},
     volume = {18},
     number = {10},
     year = {1982},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1982_18_10_a5/}
}