@article{DAN_1972_202_5_a6,
     author = {G. V. Rozenblum},
     title = {The distribution of the discrete spectrum for singular differential operators},
     journal = {Doklady Akademii Nauk},
     pages = {1012--1015},
     publisher = {mathdoc},
     volume = {202},
     number = {5},
     year = {1972},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1972_202_5_a6/}
}