1. K. Morikawa, T. Shirasaki and M. Okada, in ?Advances in Catalysis? edited by D. D. Eley, H. Pines and P. B. Weisz, Vol. 20 (Academic Press, New York, 1968) p. 97.
2. I. Furuoya and T. Shirasaki, Bull. J. Petrol. Inst. 13 (1971) 78.
3. F. Basolo and R. L. Burwell, Jr, ?Catalysis Progress in Research? (Plenum, New York, 1973).
4. M. Lo Jacono and M. Schiavello, in ?Preparation of Catalysis? edited by B. Delmon, P. A. Jacobs and J. Poncelet (Elsevier, Amsterdam, 1976) p. 473.
5. F. Bozon-Verduraz, M. Tardy, G. Bugli and G. Pamelia, in ?Preparation of Catalysis? edited by B. Delmon, P. A. Jacobs and J. Poncelot (Elsevier, Amsterdam, 1976) p. 266.