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@article{DE_1993_29_1_a12, author = {Ya. N. Mamedov}, title = {On the eigenvalue problem for equations of mixed type}, journal = {Differencialʹnye uravneni\^a}, pages = {95--103}, publisher = {mathdoc}, volume = {29}, number = {1}, year = {1993}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1993_29_1_a12/} }
Ya. N. Mamedov. On the eigenvalue problem for equations of mixed type. Differencialʹnye uravneniâ, Tome 29 (1993) no. 1, pp. 95-103. http://geodesic.mathdoc.fr/item/DE_1993_29_1_a12/