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@article{DE_1984_20_1_a6, author = {S. K. Kulazhanov}, title = {The spectrum of a mixed problem for an equation of mixed type}, journal = {Differencialʹnye uravneni\^a}, pages = {56--60}, publisher = {mathdoc}, volume = {20}, number = {1}, year = {1984}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1984_20_1_a6/} }
S. K. Kulazhanov. The spectrum of a mixed problem for an equation of mixed type. Differencialʹnye uravneniâ, Tome 20 (1984) no. 1, pp. 56-60. http://geodesic.mathdoc.fr/item/DE_1984_20_1_a6/