1. Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region, Russia
2. Dubna State University, 141982 Dubna, Moscow Region, Russia
3. Institute for Theoretical Physics II, University of Erlangen, D-91058, Erlangen, Germany
4. Institute of Physics, Slovak Academy of Sciences, 84511 Bratislava, Slovakia
5. Institute of Particle and Nuclear Physics, Charles University, CZ-18000, Praha 8, Czech Republic