@article{DAN_1975_222_1_a4,
     author = {V. Ya. Ivrii},
     title = {Well-posedness in projective {Gevrey} classes of the {Cauchy} problem for nonstrictly hyperbolic operators},
     journal = {Doklady Akademii Nauk},
     pages = {26--28},
     publisher = {mathdoc},
     volume = {222},
     number = {1},
     year = {1975},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1975_222_1_a4/}
}