1. C. Ayoub, On properties possessed by solvable and nilpotent groups,J. Austral. Math. Soc. 9 (1969), 218–227.MR 38 # 5925
2. R. Baer, Normalisatorreiche Gruppen,Rend. Sem. Mat. Univ. Padova 38 (1967), 358–450.MR 36 # 6500
3. V. S. Čarin, Ob uslovii minimal'nosti dlja normal'nyh delitelei lokal'no razrešimyh grupp (On the minimality condition for normal divisors of locally soluble groups),Mat. Sb. 33 (1953), 27–36.MR 15 — 197
4. S. N. Černikov, Beskonečnye gruppy s nekotorymi zadannymi svoistvami sistem ih beskonečnyh podgrupp (Infinite groups with certain prescribed properties of systems of infinite subgroups of them),Dokl. Akad. Nauk SSSR 159 (1964), 759–760 [Soviet Math. Dokl. 5 (1964), 1610–1611].MR 30 # 167
5. L. Iván, On groups in which each subgroup generated by two elements is finite,Period. Math. Hungar. 13 (1982), 157–162.