1. Section for Chemical Reactivity, Environmental Science and Technology Department, Risø National Laboratory, DK-4000 Roskilde, Denmark
2. Research Staff, SRL-E3083, Ford Motor Company, P.O. Box 2053, Dearborn, Michigan 48121-2053
3. Ford Forschungszentrum Aarchen, Ford Motor Company, Dennewartsstrasse 25, D-52068 Aachen, Germany