1. V. A. Pal'm, Usp. Khim.,30, 1069 (1961).
2. C. D. Johnson, The Hammett Equation, Cambridge Univ. Press (1973).
3. A. Ono, J. Chromatogr.,110, 233 (1975).
4. S. V. Vitt, E. A. Paskonova, M. G. Bezrukov, and V. B. Bondarev, Izv. Akad. Nauk SSSR, Ser. Khim., 1712 (1971).
5. R. Fellous, L. Luft, and J.-P. Rabine, J. Chromatogr.,140, 143 (1977).