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@article{IVM_1961_6_a3, author = {F. Z. Ziatdinov}, title = {On the theory of linear differential operators}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {25--31}, publisher = {mathdoc}, number = {6}, year = {1961}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1961_6_a3/} }
F. Z. Ziatdinov. On the theory of linear differential operators. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 6 (1961), pp. 25-31. http://geodesic.mathdoc.fr/item/IVM_1961_6_a3/