1. G.H. Unzelman, 1998 NPRA Annual Meeting, San Francisco, CA, 1998, p. AM-98-52.
2. T. Chang, Oil Gas J. (December 20, 1999) 34.
3. Isobutane/butene alkylation on solid catalysts. Where do we stand?
4. J.H. Gary, G.H. Handwerk, Petroleum Refining: Technology and Economics, 3rd Edition, Dekker, New York, 1994.