1. F. A. Berezin, TheMethod of Second Quantization (New York, 1966).
2. D. A. Kirznic, Field Theoretical Methods in Many-Body Theory (Gosatomizdat, Moscow, 1963).
3. N. N. Bogolyubov and D. V. Shirkov, Quantum Fields (Benjamin-Cummings Publ., 1982).
4. H. Y. Fan, “Operator ordering in quantum optics theory and the development of Dirac’s symbolic method,” J. Opt. B: Quantum Semiclass. Opt. 5, R147–R163 (2003).
5. G.W. Gardiner and P. Zoller, Quantum Noise (Springer-Verlag, Berlin, 2004).