@article{DAN_1969_185_4_a9,
     author = {F. S. Rofe-Beketov and E. Kh. Khristov},
     title = {Certain analytical questions and the inverse {Sturm{\textendash}Liouville} problem for an equation with highly singular potential},
     journal = {Doklady Akademii Nauk},
     pages = {768--771},
     year = {1969},
     volume = {185},
     number = {4},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1969_185_4_a9/}
}