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@article{DE_1969_5_2_a16, author = {N. A. Lukashevich}, title = {Functions which are definable by a certain system of differential equations}, journal = {Differencialʹnye uravneni\^a}, pages = {379--381}, publisher = {mathdoc}, volume = {5}, number = {2}, year = {1969}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1969_5_2_a16/} }
N. A. Lukashevich. Functions which are definable by a certain system of differential equations. Differencialʹnye uravneniâ, Tome 5 (1969) no. 2, pp. 379-381. http://geodesic.mathdoc.fr/item/DE_1969_5_2_a16/