1. D. P. Burke, Chem. Week, (March 28, 1979) p. 42 and (April 4, 1979) p. 46.
2. J. P. Anderson, ?Structure of metallic catalysts? (Academic Press, New York and London, 1975).
3. R. L. Moss, in ?Experimental Methods in Catalytic Research?, Vol. 2, edited by R. B. Anderson and P. T. Dawson (Academic Press, New York and London, 1976).
4. F. Garbassi, A. Bossi, A. Orlandi, G. Petrini and L. Zanderighi, Ned. Tijdsch. Vacuumtechn. 16 (1978) 35.
5. A. Bossi, F. Garbassi, A. Orlandi, G. Petrini and L. Zanderighi, in ?Preparation of Catalysts II?, edited by B. Delman, P. Grange, P. Jacobs and G. Poncelet (Elsevier, Amsterdam, 1979) p. 405.