1. The Theory of Groups;Hall,1959
2. Engelsche Elemente der Länge drei;Heineren;Illinois J. Math.,1961
3. Finite groups with normal normalizers;Hobby;Canad. J. Math.,1968
4. Die A-Norm einer Gruppe;Kappe;Illinois J. Math.,1961
5. Groups in which the commutator operation satisfies certain algebraic conditions;Levi;J.Indian Math. Soc Ser. 2,1942