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@article{DE_1978_14_8_a22, author = {\`E. I. Grudo}, title = {A method for lowering the order of linear differential equations}, journal = {Differencialʹnye uravneni\^a}, pages = {1514--1515}, publisher = {mathdoc}, volume = {14}, number = {8}, year = {1978}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1978_14_8_a22/} }
È. I. Grudo. A method for lowering the order of linear differential equations. Differencialʹnye uravneniâ, Tome 14 (1978) no. 8, pp. 1514-1515. http://geodesic.mathdoc.fr/item/DE_1978_14_8_a22/