@article{MZM_1991_49_6_a2,
     author = {A. B. Budak and V. N. Denisov},
     title = {Properties of the spectral function of a {Sturm{\textendash}Liouville} operator with discontinuous coefficients},
     journal = {Matemati\v{c}eskie zametki},
     pages = {19--28},
     year = {1991},
     volume = {49},
     number = {6},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1991_49_6_a2/}
}