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@article{DE_2004_40_6_a0, author = {E. E. Bukzhalev}, title = {On the {Construction} of {Upper} and {Lower} {Solutions} by the {Nagumo} {Method}}, journal = {Differencialʹnye uravneni\^a}, pages = {723--730}, publisher = {mathdoc}, volume = {40}, number = {6}, year = {2004}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_2004_40_6_a0/} }
E. E. Bukzhalev. On the Construction of Upper and Lower Solutions by the Nagumo Method. Differencialʹnye uravneniâ, Tome 40 (2004) no. 6, pp. 723-730. http://geodesic.mathdoc.fr/item/DE_2004_40_6_a0/