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@article{SEMR_2006_3_a15, author = {D. V. Solomatin}, title = {Direct products of cyclic semigroups admitting a~planar {Caley} graph}, journal = {Sibirskie \`elektronnye matemati\v{c}eskie izvesti\^a}, pages = {238--252}, publisher = {mathdoc}, volume = {3}, year = {2006}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/SEMR_2006_3_a15/} }
D. V. Solomatin. Direct products of cyclic semigroups admitting a~planar Caley graph. Sibirskie èlektronnye matematičeskie izvestiâ, Tome 3 (2006), pp. 238-252. http://geodesic.mathdoc.fr/item/SEMR_2006_3_a15/