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@article{PORMA_1990__47_1_115699, author = {Volenec, Vladimir}, title = {Subtractive groupoids and laterally commutative heaps}, journal = {Portugaliae mathematica}, pages = {43--45}, publisher = {mathdoc}, volume = {47}, number = {1}, year = {1990}, mrnumber = {1079505}, zbl = {0716.20044}, language = {en}, url = {http://geodesic.mathdoc.fr/item/PORMA_1990__47_1_115699/} }
Volenec, Vladimir. Subtractive groupoids and laterally commutative heaps. Portugaliae mathematica, Tome 47 (1990) no. 1, pp. 43-45. http://geodesic.mathdoc.fr/item/PORMA_1990__47_1_115699/