@article{SF_1974__9_134078,
     author = {M. Petrich},
     title = {Inner automorphisms of the translational hull.},
     journal = {Semigroup forum},
     pages = {209--215},
     year = {1974},
     volume = {9},
     zbl = {0334.20041},
     url = {http://geodesic.mathdoc.fr/item/SF_1974__9_134078/}
}