@article{FAA_1975_9_4_a6,
     author = {M. I. Belishev},
     title = {Infringement of the condition for solvability of the converse problem for an inhomogeneous string},
     journal = {Funkcionalʹnyj analiz i ego prilo\v{z}eni\^a},
     pages = {57--58},
     publisher = {mathdoc},
     volume = {9},
     number = {4},
     year = {1975},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/FAA_1975_9_4_a6/}
}