1. N. Bourbaki, Lie Groups and Algebras, IV–VI [Russian translation], Mir, Moscow (1972).
2. R. Carter, Simple Groups of Lie Type, Wiley, New York (1972).
3. J. A. Gibbs, “Automorphisms of certain unipotent groups,” J. Algebra, 14, No. 2, 203–228 (1970).
4. M. Hall, Group Theory [Russian translation], Inostr. Lit., Moscow (1962).
5. The Kourovka Notebook. Unsolved Problems in Group Theory [in Russian], 15th ed., Institute of Mathematics, Novosibirsk (2002).