@article{DAN_1967_176_4_a11,
     author = {E. N. Rozenvasser},
     title = {A method for investigating the stability of a system of linear differential equations with periodic coefficients},
     journal = {Doklady Akademii Nauk},
     pages = {783--786},
     year = {1967},
     volume = {176},
     number = {4},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1967_176_4_a11/}
}