%0 Journal Article %A LONGOBARDI, PATRIZIA %A MAJ, MERCEDE %A ROBINSON, DEREK J. S. %A SMITH, HOWARD %T ON GROUPS WITH TWO ISOMORPHISM CLASSES OF DERIVED SUBGROUPS %J Glasgow mathematical journal %D 2013 %P 655-668 %V 55 %N 3 %U http://geodesic.mathdoc.fr/articles/10.1017/S0017089512000821/ %R 10.1017/S0017089512000821 %F 10_1017_S0017089512000821