@article{SF_1982__25_134582,
     author = {N.M. Khan},
     title = {Epimorphisms, dominions and varieties of semigroups.},
     journal = {Semigroup forum},
     pages = {331--338},
     publisher = {mathdoc},
     volume = {25},
     year = {1982},
     zbl = {0496.20049},
     url = {http://geodesic.mathdoc.fr/item/SF_1982__25_134582/}
}