@article{FPM_1999_5_2_a3,
     author = {V. V. Dubrovskii and L. V. Smirnova},
     title = {On~singularity of solution to inverse problems of spectral analysis expressed with equations of mathematical physics},
     journal = {Fundamentalʹna\^a i prikladna\^a matematika},
     pages = {411--416},
     publisher = {mathdoc},
     volume = {5},
     number = {2},
     year = {1999},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/FPM_1999_5_2_a3/}
}