1. G.J. Hutchings, New Scientist, (July 3, 1986) 35.
2. 3 S.A. Tabak and F.J. Krambeck, Hydrocarbon Process., (Sept. 1985) 72.
3. G.C. Diaz, L. Ortiz and F. Villegas, in Symp. on Recent Advances in the Production and Utilization of Light Olefins, Anaheim Meeting, Am. Chem. Soc.,
4. Dimerization of olefins with nickel-surface complexes in X-type zeolite or on silica