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@article{DAN_1989_304_2_a6, author = {Nguyen Thi Thien Hoa}, title = {The oscillation property of the operator $D(D^2+1^2)\cdots}, journal = {Doklady Akademii Nauk}, pages = {289--293}, publisher = {mathdoc}, volume = {304}, number = {2}, year = {1989}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1989_304_2_a6/} }
Nguyen Thi Thien Hoa. The oscillation property of the operator $D(D^2+1^2)\cdots. Doklady Akademii Nauk, Tome 304 (1989) no. 2, pp. 289-293. http://geodesic.mathdoc.fr/item/DAN_1989_304_2_a6/