1. Ya. B. Zel'dovich and I. D. Novikov, The Structure and Evolution of the Universe [in Russian], Nauka, Moscow (1975).
2. V. A. Zhelnorovich, Theory of Spinors and Its Application in Physics and Mechanics [in Russian], Nauka, Moscow (1982).
3. N. N. Bogolyubov and D. V. Shirkov, Introduction to Quantum Field Theory [in Russian] Nauka, Moscow (1976).