1. Chunikhin, S.A.: ‘On π-separable groups’, Dokl. Akad. Nauk SSSR 59, no. 3 (1948), 443–445 (in Russian).
2. Hall, P.: ‘Theorems like Sylow’s’, Proc. London Math. Soc. 6, no. 22 (1956), 286–304.
3. Kurosh, A.G.: The theory of groups, II, Chelsea, 1955-1956, p. 195ff (translated from the Russian).
4. Gol’berg, P.A.: ‘Sylow bases of π-separable groups’, Dokl. Akad. Nauk SSSR 60 (1949), 615–618 (in Russian).
5. Chunikhin, S.A.: ‘On π-properties of finite groups’, Mat. Sb. 25 (1949), 321–346 (in Russian).