1. Johnson, C.D., The Hammett Equation, Cambridge: Cambridge Univ. Press, 1973.
2. Suvorov, B.A., Zh. Obshch. Khim., 2003, vol. 73, no. 1, p. 126.
3. Suvorov, B.A., Zh. Obshch. Khim., 2003, vol. 73, no. 11, p. 1876.
4. Suvorov, B.A., Zh. Fiz. Khim., 2003, vol. 77, no. 7, p. 1222.
5. Ruedenberg, K., The Physical Nature of the Chemical Bond, Rev. Mod. Phys., 1962, vol. 24, p. 326.