1. Danish Polymer Centre, Risø National Laboratory, POL 124, PO Box 49, 4000 Roskilde, Denmark
2. Danish Polymer Centre, Risø National Laboratory, POL 124, PO Box 49, 4000 Roskilde, Denmark,
3. SRI International, 333 Ravenswood Avenue, EJ345, Menlo Park, CA 94025, USA