1. H.W. Streitwolf, Group Theory in Solid State Physics (MacDonald, London, 1971)
2. W.A. Harrison, Electronic Structure and the Properties of Solids, 2nd edn. (Dover, New York, 1989)
3. J. Callaway, Quantum Theory of the Solid State, 2nd edn. (Academic, New York, 1991)
4. R.M. Martin, Electronic Structure: Basic Theory and Practical Methods, 2nd edn. (Cambridge University Press, Cambridge, 2020)
5. S.G. Mikhlin, Variational Methods in Mathematical Physics [in Russian], 2nd edn. (Nauka, Moscow, 1970). Engl. transl.: Pergamon, Oxford, 1964