@article{DAN_1957_114_1_a1,
     author = {V. G. Egorov},
     title = {The stability of the solutions of periodical systems of total differential equations},
     journal = {Doklady Akademii Nauk},
     pages = {11--13},
     publisher = {mathdoc},
     volume = {114},
     number = {1},
     year = {1957},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1957_114_1_a1/}
}