1. Czech Technical University, 166-27 Prague, Czech Republic
2. Institute of Plasma Physics and Laser Microfusion, 01-497 Warsaw, Poland
3. National Centre for Nuclear Research, 05-400 Otwock-Świerk, Poland
4. ACS Ltd., 01-497 Warsaw, Poland
5. Department of Physics, Atomic Energy Commission, P.O. Box 6091, Damascus, Syria