1. E. G. Rozantsev, Iminoxyl Free Radicals [in Russian], Khimiya, Moscow (1970).
2. A. L. Buchachenio and A. M. Vasserman, Stable Radicals [in Russian], Khimiya, Moscow (1973).
3. A. N. Kuznetsov, The Spin Probe Method [in Russian], Nauka, Moscow (1976).
4. R. P. Sibaeva, Zh. Strukt. Khim.,16, 330 (1975).
5. R. Briere, A. Rassat, and P. Rey, J. Chim. Phys.,63, 1575 (1966).