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@article{IVM_1981_9_a6, author = {L. M. Martynov}, title = {Attainable classes of semigroups with zero}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {29--37}, publisher = {mathdoc}, number = {9}, year = {1981}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1981_9_a6/} }
L. M. Martynov. Attainable classes of semigroups with zero. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 9 (1981), pp. 29-37. http://geodesic.mathdoc.fr/item/IVM_1981_9_a6/