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A. Ballester-Bolinches, S. F. Kamornikov, V. N. Tyutyanov
On a problem of L.A. Shemetkov on superradical formations of finite groups
J. Algebra, 403, 69-76 (2014)
http://dx.doi.org/10.1016/j.jalgebra.2014.01.004
Abstract: Subgroup-closed saturated formations F which are closed under taking products of F-subnormal F-subgroups are studied in the paper. Our results can be regarded as further developments in the hunt for a solution of a problem proposed by L.A. Shemetkov in 1999 in the Kourovka Notebook.
MSC: 20D10, 20D20
Keywords: Finite group, saturated formation, critical group