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@article{DE_1977_13_7_a25, author = {B. Puzha}, title = {A comparison theorem for systems of two differential equations}, journal = {Differencialʹnye uravneni\^a}, pages = {1338--1340}, publisher = {mathdoc}, volume = {13}, number = {7}, year = {1977}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1977_13_7_a25/} }
B. Puzha. A comparison theorem for systems of two differential equations. Differencialʹnye uravneniâ, Tome 13 (1977) no. 7, pp. 1338-1340. http://geodesic.mathdoc.fr/item/DE_1977_13_7_a25/