@article{SF_1994__49_2_135332,
     author = {K. Denecke and J. Koppitz},
     title = {Hyperassociative varieties of semigroups.},
     journal = {Semigroup forum},
     pages = {41--48},
     publisher = {mathdoc},
     volume = {49},
     number = {2},
     year = {1994},
     zbl = {0806.20049},
     url = {http://geodesic.mathdoc.fr/item/SF_1994__49_2_135332/}
}