@article{DAN_1991_319_2_a0,
     author = {R. Kh. Amirov},
     title = {A multidimensional inverse problem for a hyperbolic equation and a},
     journal = {Doklady Akademii Nauk},
     pages = {265--266},
     publisher = {mathdoc},
     volume = {319},
     number = {2},
     year = {1991},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1991_319_2_a0/}
}