@article{ARM_1995_31_1_a4,
     author = {Ku\v{r}il, Martin},
     title = {A multiplication of $e$-varieties of orthodox semigroups},
     journal = {Archivum mathematicum},
     pages = {43--54},
     year = {1995},
     volume = {31},
     number = {1},
     mrnumber = {1342374},
     zbl = {0836.20084},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/ARM_1995_31_1_a4/}
}