@article{DAN_1965_161_4_a6,
     author = {V. B. Lidskii and P. A. Frolov},
     title = {The topological structure of stability-regions of a self-adjoint system of differential equations with periodic coefficients},
     journal = {Doklady Akademii Nauk},
     pages = {764--766},
     publisher = {mathdoc},
     volume = {161},
     number = {4},
     year = {1965},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1965_161_4_a6/}
}