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@article{AL_1970_9_6_a10, author = {D. J. Collins}, title = {A universal semigroup}, journal = {Algebra i logika}, pages = {731--740}, publisher = {mathdoc}, volume = {9}, number = {6}, year = {1970}, language = {en}, url = {http://geodesic.mathdoc.fr/item/AL_1970_9_6_a10/} }
D. J. Collins. A universal semigroup. Algebra i logika, Tome 9 (1970) no. 6, pp. 731-740. http://geodesic.mathdoc.fr/item/AL_1970_9_6_a10/