@article{DE_1970_6_3_a4,
     author = {S. S. Belyavsky},
     title = {Conditional stability on a finite interval of time},
     journal = {Differencialʹnye uravneni\^a},
     pages = {431--434},
     publisher = {mathdoc},
     volume = {6},
     number = {3},
     year = {1970},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1970_6_3_a4/}
}