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@article{MZM_1978_24_2_a9, author = {V. G. Romanov}, title = {A~statement of the converse problem for first-order symmetric hyperbolic systems}, journal = {Matemati\v{c}eskie zametki}, pages = {231--236}, publisher = {mathdoc}, volume = {24}, number = {2}, year = {1978}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MZM_1978_24_2_a9/} }
V. G. Romanov. A~statement of the converse problem for first-order symmetric hyperbolic systems. Matematičeskie zametki, Tome 24 (1978) no. 2, pp. 231-236. http://geodesic.mathdoc.fr/item/MZM_1978_24_2_a9/