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@article{DE_1973_9_3_a6, author = {A. K. Ratyni}, title = {Differential inequalities for the {Sturm--Liouville} problem}, journal = {Differencialʹnye uravneni\^a}, pages = {456--464}, publisher = {mathdoc}, volume = {9}, number = {3}, year = {1973}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1973_9_3_a6/} }
A. K. Ratyni. Differential inequalities for the Sturm--Liouville problem. Differencialʹnye uravneniâ, Tome 9 (1973) no. 3, pp. 456-464. http://geodesic.mathdoc.fr/item/DE_1973_9_3_a6/