@article{DE_1968_4_7_a9,
     author = {N. V. Medvedev},
     title = {Certain criteria for the existence of bounded solutions of a system of differential equations},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1258--1264},
     publisher = {mathdoc},
     volume = {4},
     number = {7},
     year = {1968},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1968_4_7_a9/}
}