@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/}
}