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@article{MZM_1995_57_2_a17, author = {A. R. Sagitova}, title = {On the deficiency indices of a~differential operator of fourth order}, journal = {Matemati\v{c}eskie zametki}, pages = {313--314}, publisher = {mathdoc}, volume = {57}, number = {2}, year = {1995}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MZM_1995_57_2_a17/} }
A. R. Sagitova. On the deficiency indices of a~differential operator of fourth order. Matematičeskie zametki, Tome 57 (1995) no. 2, pp. 313-314. http://geodesic.mathdoc.fr/item/MZM_1995_57_2_a17/
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