@article{DAN_1991_316_2_a8,
     author = {Ya. A. Roitberg},
     title = {The {Cauchy} problem for general hyperbolic systems in a complete scale of {Sobolev-type} spaces},
     journal = {Doklady Akademii Nauk},
     pages = {300--304},
     publisher = {mathdoc},
     volume = {316},
     number = {2},
     year = {1991},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1991_316_2_a8/}
}