Tuna Alt{\i}nel, Alexandre Borovik, Gregory Cherlin, “On Groups of Finite Morley Rank with Weakly Embedded Subgroups”, Journal of Algebra, 211:2 (1999), 409
A. V. Borovik, Algebraic Groups and their Representations, 1998, 341
С. А. Сыскин, “Конечные группы с примарными централизаторами четверных подгрупп”, Изв. АН СССР. Сер. матем., 42:5 (1978), 1132–1150; S. A. Syskin, “Finite groups in which centralizers of four-subgroups are 2-groups”, Math. USSR-Izv., 13:2 (1979), 417–434