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@article{IVM_1989_12_a13, author = {E. S. Lyapin}, title = {The possibility of semigroup continuation of a~partial groupoid}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {68--70}, publisher = {mathdoc}, number = {12}, year = {1989}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1989_12_a13/} }
E. S. Lyapin. The possibility of semigroup continuation of a~partial groupoid. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 12 (1989), pp. 68-70. http://geodesic.mathdoc.fr/item/IVM_1989_12_a13/