1. Baer, R.: Finite extensions of Abelian groups with minimum condition. Amer. Math. Soc. Translat.79, 521?540 (1955).
2. Baumslag, G.: Wreath products andp-groups. Proc. Cambridge Philos. Soc.55, 224?231 (1959).
3. ?ernikov, S. N.: On the centralizer of a complete Abelian normal subgroup in an infinite periodic group. Doklady Akad. Nauk SSSR72, 243?246 (1950).
4. ? Endlichkeitsbedingungen in der Gruppentheorie. Berlin: VEB Deutscher Verlag der Wissenschaften 1963. (Translation from Uspehi Mat. Nauk14, Nr. 5 (89), 45?96 (1959).
5. ? On periodic groups of automorphisms of extremal groups. Mat. Zametki.4, 91?96 (1968).