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@article{MZM_1992_51_4_a10, author = {I. V. Mustyatsa}, title = {Union of derivative chains of two quadratic pencils of unbounded operators}, journal = {Matemati\v{c}eskie zametki}, pages = {85--90}, publisher = {mathdoc}, volume = {51}, number = {4}, year = {1992}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MZM_1992_51_4_a10/} }
I. V. Mustyatsa. Union of derivative chains of two quadratic pencils of unbounded operators. Matematičeskie zametki, Tome 51 (1992) no. 4, pp. 85-90. http://geodesic.mathdoc.fr/item/MZM_1992_51_4_a10/