@article{DE_1991_27_3_a1,
     author = {N. V. Azbelev and A. I. Domoshnitskii},
     title = {On the question of linear differential inequalities. {I}},
     journal = {Differencialʹnye uravneni\^a},
     pages = {376--384},
     publisher = {mathdoc},
     volume = {27},
     number = {3},
     year = {1991},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1991_27_3_a1/}
}