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@article{DE_1977_13_11_a5, author = {A. M. Zverkin}, title = {Comparison theorems for oscillatory solutions of equations with lag}, journal = {Differencialʹnye uravneni\^a}, pages = {1951--1956}, publisher = {mathdoc}, volume = {13}, number = {11}, year = {1977}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1977_13_11_a5/} }
A. M. Zverkin. Comparison theorems for oscillatory solutions of equations with lag. Differencialʹnye uravneniâ, Tome 13 (1977) no. 11, pp. 1951-1956. http://geodesic.mathdoc.fr/item/DE_1977_13_11_a5/