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@article{MZM_1980_28_4_a4, author = {S. P. Belinskii and V. G. Romanov}, title = {Determination of the coefficients of a $t$-hyperbolic system}, journal = {Matemati\v{c}eskie zametki}, pages = {525--532}, publisher = {mathdoc}, volume = {28}, number = {4}, year = {1980}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MZM_1980_28_4_a4/} }
S. P. Belinskii; V. G. Romanov. Determination of the coefficients of a $t$-hyperbolic system. Matematičeskie zametki, Tome 28 (1980) no. 4, pp. 525-532. http://geodesic.mathdoc.fr/item/MZM_1980_28_4_a4/