@article{DE_1991_27_10_a18,
     author = {A. F. Ulitko and A. G. Kiselevskii and L. Shorfi},
     title = {Discrete spectrum of the {Sturm--Liouville} operator in the third boundary value problem for a truncated one-sheeted hyperboloid of revolution},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1807--1812},
     publisher = {mathdoc},
     volume = {27},
     number = {10},
     year = {1991},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1991_27_10_a18/}
}