1. P.A.M. Dirac, The Principles of Quantum Mechanics, 4th edn. (Oxford University Press, Oxford, 1982)
2. J. Cornwell, Group Theory and Eectronic Energy Bands in Solids (John Wiley and Sons, New York, 1969)
3. J.R. Chelikowsky, M.L. Cohen, Phys. Rev. B14, 556–582 (1976)
4. J.D. Jackson, Classical Electrodynamics, 3rd edn. (John Wiley & Sons, New York, 1999)
5. Refer, for example, to Chapter 11 in it Quantum Mechanics, 3rd ed. by L. I. Sciff (Mc-Grawhill Inc., New York, 1955–1969).