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@article{IVM_1975_4_a2, author = {A. K. Guts}, title = {Mappings of families of sets in {a~Loba\v{c}evski\u\i\} space}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {24--32}, publisher = {mathdoc}, number = {4}, year = {1975}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1975_4_a2/} }
A. K. Guts. Mappings of families of sets in a~Loba\v{c}evski\u\i\ space. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 4 (1975), pp. 24-32. http://geodesic.mathdoc.fr/item/IVM_1975_4_a2/