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@article{IVM_1981_4_a5, author = {P. I. Kovalev}, title = {Operators in {Lobachevskii} space}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {29--33}, publisher = {mathdoc}, number = {4}, year = {1981}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1981_4_a5/} }
P. I. Kovalev. Operators in Lobachevskii space. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 4 (1981), pp. 29-33. http://geodesic.mathdoc.fr/item/IVM_1981_4_a5/