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@article{IVM_1957_1_a7, author = {V. V. Vagner}, title = {Semigroups of partial mappings with a~symmetric transitivity relation}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {81--88}, publisher = {mathdoc}, number = {1}, year = {1957}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1957_1_a7/} }
V. V. Vagner. Semigroups of partial mappings with a~symmetric transitivity relation. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 1 (1957), pp. 81-88. http://geodesic.mathdoc.fr/item/IVM_1957_1_a7/