@article{DE_1984_20_12_a18,
     author = {N. G. Bulgakov},
     title = {Stability in the large of a second-order periodic system of general form},
     journal = {Differencialʹnye uravneni\^a},
     pages = {2158--2161},
     publisher = {mathdoc},
     volume = {20},
     number = {12},
     year = {1984},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1984_20_12_a18/}
}