1. U.S. 3, 343, 952.
2. Ger. 1. 811, 062.
3. Jap. 6, 927, 202.
4. G.K. Boreskov, S.A. Venyaminov, V.A. Dzisko, D.V. Tarasova, N.N. Sazonova, J.P. Olenkova, L.M. Kefeli: Kinet. Katal.,11, 153 (1970).
5. V.P. Shchukin, S.A. Venyaminov, G.K. Boreskov: Kinet. Katal.,12, 621 (1971).