@article{DE_1971_7_2_a18,
     author = {G. S. Krechetov},
     title = {The perturbations that preserve the stability property},
     journal = {Differencialʹnye uravneni\^a},
     pages = {363--364},
     publisher = {mathdoc},
     volume = {7},
     number = {2},
     year = {1971},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1971_7_2_a18/}
}