@article{DAN_1967_172_6_a3,
     author = {Ya. I. Zhitomirskii},
     title = {Classes of uniqueness of solution of the {Cauchy} problem},
     journal = {Doklady Akademii Nauk},
     pages = {1258--1261},
     publisher = {mathdoc},
     volume = {172},
     number = {6},
     year = {1967},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1967_172_6_a3/}
}