1. FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, Trilateral Euregio Cluster P.O. Box 1207, 3430 BE Nieuwegein, The Netherlands (〈〉)
2. Institut für Plasmaphysik, Forschungszentrum Jülich GmbH, EURATOM Association, Trilateral Euregio Cluster D-52425 Jülich, Germany
3. Optics and Fluid Dynamics Department, Ass. Euratom-National Laboratory Risø, DK-4000 Roskilde, Denmark
4. Laboratory for Plasma Physics, Ecole Royale Militaire-Koninklijke Militaire School Association EURATOM-Belgian State, Trilateral Euregio Cluster, B-1000 Brussels, Belgium