1. B. Puhlmann and A. Puhlmann, Quantum Biochemistry [Russian translation], Mir, Moscow (1965), p. 388.
2. A. Szent-György, Introduction to Submolecular Biology [Russian translation], Nauka, Moscow (1964), p. 79.
3. L. Andrews and R. Kiefer, Molecular Complexes in Organic Chemistry (Russian translation], Mir, Moscow (1967), pp. 17, 70.
4. E. Fischerand and G. Werner, ?-Complexes of Metals [Russian translation], Mir, Moscow (1968), p. 84.
5. I. M. Ginzburg and V. R. Khlevnyuk, Opt. i Spektrosk.,24, 816 (1968).