@article{MZ_1971__123_171632,
     author = {Michael Friedberg},
     title = {Homomorphisms of {Divisible} {Semigroups.}},
     journal = {Mathematische Zeitschrift},
     pages = {215--218},
     publisher = {mathdoc},
     volume = {123},
     year = {1971},
     zbl = {0221.20084},
     url = {http://geodesic.mathdoc.fr/item/MZ_1971__123_171632/}
}