@article{MZ_1978__164_172778,
     author = {Daniel Segal},
     title = {Two {Theorems} on {Polycyclic} {Groups.}},
     journal = {Mathematische Zeitschrift},
     pages = {185--188},
     year = {1978},
     volume = {164},
     zbl = {0391.20026},
     url = {http://geodesic.mathdoc.fr/item/MZ_1978__164_172778/}
}