1. I. B. Bersuker, The Electronic Structure and Properties of Coordination Compounds. An Introduction to the Theory [in Russian], 2nd edition, Khimiya, Leningrad (1976).
2. C. J. Ballhausen, Introduction to Ligand Field Theory [Russian translation], Mir, Moscow (1964).
3. N. M. Klimenko, Quantum-Chemical Calculations for Transition Metal Compounds. Progress in Science and Technology. Series: The Structure of Molecules and the Chemical Bond [in Russian], Vol. 6, VINITI, Moscow (1978).
4. V. I. Nefedov, The Valence Electron Levels of Chemical Compounds. Progress in Science and Technology. Series: The Structure of Molecules and the Chemical Bond [in Russian], Vol. 3, VINITI, Moscow (1975).
5. V. I. Nefedov, The X-Ray Spectroscopy of Chemical Compounds [in Russian], Khimiya, Moscow (1984).