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@article{DE_1970_6_6_a7, author = {L. S. Lavrinovich}, title = {A certain class of systems of two differential equations}, journal = {Differencialʹnye uravneni\^a}, pages = {1017--1025}, publisher = {mathdoc}, volume = {6}, number = {6}, year = {1970}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1970_6_6_a7/} }
L. S. Lavrinovich. A certain class of systems of two differential equations. Differencialʹnye uravneniâ, Tome 6 (1970) no. 6, pp. 1017-1025. http://geodesic.mathdoc.fr/item/DE_1970_6_6_a7/