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@article{DE_1987_23_6_a7, author = {A. A. Stakun}, title = {On the properties of a differential operator with a multiple turning point}, journal = {Differencialʹnye uravneni\^a}, pages = {993--999}, publisher = {mathdoc}, volume = {23}, number = {6}, year = {1987}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1987_23_6_a7/} }
A. A. Stakun. On the properties of a differential operator with a multiple turning point. Differencialʹnye uravneniâ, Tome 23 (1987) no. 6, pp. 993-999. http://geodesic.mathdoc.fr/item/DE_1987_23_6_a7/