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@article{DE_1978_14_3_a4, author = {A. M. Zverkin}, title = {The spectrum of a degenerate boundary value problem}, journal = {Differencialʹnye uravneni\^a}, pages = {435--441}, publisher = {mathdoc}, volume = {14}, number = {3}, year = {1978}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1978_14_3_a4/} }
A. M. Zverkin. The spectrum of a degenerate boundary value problem. Differencialʹnye uravneniâ, Tome 14 (1978) no. 3, pp. 435-441. http://geodesic.mathdoc.fr/item/DE_1978_14_3_a4/