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@article{DE_1969_5_7_a8, author = {R. S. Levitin}, title = {Frommer's first distinguishing problem for perturbations from {Osgood} and {Tamarkin} classes}, journal = {Differencialʹnye uravneni\^a}, pages = {1236--1246}, publisher = {mathdoc}, volume = {5}, number = {7}, year = {1969}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1969_5_7_a8/} }
R. S. Levitin. Frommer's first distinguishing problem for perturbations from Osgood and Tamarkin classes. Differencialʹnye uravneniâ, Tome 5 (1969) no. 7, pp. 1236-1246. http://geodesic.mathdoc.fr/item/DE_1969_5_7_a8/