@article{DE_1989_25_10_a1,
     author = {E. A. Barabanov},
     title = {Necessary conditions for the simultaneous behavior of higher sigma-exponents of a triangular system and systems of its diagonal approximation},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1662--1670},
     publisher = {mathdoc},
     volume = {25},
     number = {10},
     year = {1989},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1989_25_10_a1/}
}