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@article{DE_1977_13_6_a21, author = {I. I. Martynov}, title = {Systems with a piecewise constant matrix of coefficients}, journal = {Differencialʹnye uravneni\^a}, pages = {1135--1137}, publisher = {mathdoc}, volume = {13}, number = {6}, year = {1977}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1977_13_6_a21/} }
I. I. Martynov. Systems with a piecewise constant matrix of coefficients. Differencialʹnye uravneniâ, Tome 13 (1977) no. 6, pp. 1135-1137. http://geodesic.mathdoc.fr/item/DE_1977_13_6_a21/