@article{IVM_1976_6_a15,
     author = {V. N. Klimov},
     title = {Congruences of semigroups},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {114--117},
     year = {1976},
     number = {6},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_1976_6_a15/}
}