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@article{DE_1973_9_3_a5, author = {N. A. Lukashevich and V. I. Matatov}, title = {Second order systems without moving critical singular points}, journal = {Differencialʹnye uravneni\^a}, pages = {449--455}, publisher = {mathdoc}, volume = {9}, number = {3}, year = {1973}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1973_9_3_a5/} }
N. A. Lukashevich; V. I. Matatov. Second order systems without moving critical singular points. Differencialʹnye uravneniâ, Tome 9 (1973) no. 3, pp. 449-455. http://geodesic.mathdoc.fr/item/DE_1973_9_3_a5/