@article{DE_1989_25_2_a25,
     author = {A. M. Nurmatov},
     title = {Necessary conditions for stability of characteristic {Lyapunov} exponents of linear differential systems in case of exponentially decreasing perturbations},
     journal = {Differencialʹnye uravneni\^a},
     pages = {335--336},
     publisher = {mathdoc},
     volume = {25},
     number = {2},
     year = {1989},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1989_25_2_a25/}
}