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@article{IVM_1959_6_a5, author = {L. S. Dashnits}, title = {On the closure of certain differential operators}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {44--47}, publisher = {mathdoc}, number = {6}, year = {1959}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1959_6_a5/} }
L. S. Dashnits. On the closure of certain differential operators. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 6 (1959), pp. 44-47. http://geodesic.mathdoc.fr/item/IVM_1959_6_a5/