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@article{DE_1977_13_7_a24, author = {V. S. Mokeichev}, title = {A criterion for the solvability of certain periodic boundary value problems}, journal = {Differencialʹnye uravneni\^a}, pages = {1335--1337}, publisher = {mathdoc}, volume = {13}, number = {7}, year = {1977}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1977_13_7_a24/} }
V. S. Mokeichev. A criterion for the solvability of certain periodic boundary value problems. Differencialʹnye uravneniâ, Tome 13 (1977) no. 7, pp. 1335-1337. http://geodesic.mathdoc.fr/item/DE_1977_13_7_a24/