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@article{DE_1968_4_11_a7, author = {N. F. Trubitsyn}, title = {A test of stability of linear systems with variable coefficients}, journal = {Differencialʹnye uravneni\^a}, pages = {1994--2001}, publisher = {mathdoc}, volume = {4}, number = {11}, year = {1968}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1968_4_11_a7/} }
N. F. Trubitsyn. A test of stability of linear systems with variable coefficients. Differencialʹnye uravneniâ, Tome 4 (1968) no. 11, pp. 1994-2001. http://geodesic.mathdoc.fr/item/DE_1968_4_11_a7/