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3. Ya. S. Lebedev, Dissertation, IKhF, AN SSSR, Moscow, 1962.
4. Atlas of Electron Paramagnetic Resonance Spectra [in Russian], no. 2, Nauka, Moscow, 1964.
5. A. Streitweiser, Molecular Orbital Theory for Organic Chemists [Russian translation], Mir, Moscow, 1965.