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@article{DE_1983_19_10_a29, author = {G. N. Petrovskiǐ}, title = {Orthogonally similar systems of linear differential equations}, journal = {Differencialʹnye uravneni\^a}, pages = {1823--1826}, publisher = {mathdoc}, volume = {19}, number = {10}, year = {1983}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1983_19_10_a29/} }
G. N. Petrovskiǐ. Orthogonally similar systems of linear differential equations. Differencialʹnye uravneniâ, Tome 19 (1983) no. 10, pp. 1823-1826. http://geodesic.mathdoc.fr/item/DE_1983_19_10_a29/