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@article{DE_1989_25_1_a11, author = {E. I. Moiseev}, title = {Disposition of the spectrum of the {Tricomi} problem for the {Lavrent'ev--Bitsadze} equation}, journal = {Differencialʹnye uravneni\^a}, pages = {97--106}, publisher = {mathdoc}, volume = {25}, number = {1}, year = {1989}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1989_25_1_a11/} }
E. I. Moiseev. Disposition of the spectrum of the Tricomi problem for the Lavrent'ev--Bitsadze equation. Differencialʹnye uravneniâ, Tome 25 (1989) no. 1, pp. 97-106. http://geodesic.mathdoc.fr/item/DE_1989_25_1_a11/