@article{DE_1973_9_5_a23,
     author = {V. N. Laptinskii},
     title = {Inequalities of the {Wa\.zewski} inequality type for the system $x^{''}=A(t)x$},
     journal = {Differencialʹnye uravneni\^a},
     pages = {961--964},
     year = {1973},
     volume = {9},
     number = {5},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1973_9_5_a23/}
}