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@article{DE_2005_41_8_a7, author = {Yu. A. Klokov}, title = {On {Upper} and {Lower} {Functions} for a {Fourth-Order} {Ordinary} {Differential} {Equation:} {I}}, journal = {Differencialʹnye uravneni\^a}, pages = {1074--1083}, publisher = {mathdoc}, volume = {41}, number = {8}, year = {2005}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_2005_41_8_a7/} }
Yu. A. Klokov. On Upper and Lower Functions for a Fourth-Order Ordinary Differential Equation: I. Differencialʹnye uravneniâ, Tome 41 (2005) no. 8, pp. 1074-1083. http://geodesic.mathdoc.fr/item/DE_2005_41_8_a7/