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2. English translation: Ukr. Math. J., 54, No. 5, 1181-1191 (2002).
3. D. Gorenstein, Finite Simple Groups. An Introduction to Their Classification [Russian translation], Mir, Moscow (1975).
4. B. Huppert, Endliche Gruppen, I, Springer, Berlin (1967).
5. F. Gross, “Hall subgroups of order not divisible by 3,” Rocky Mountain J. Math., 23, No. 2, 569–591 (1993).