1. Polar Geophysical Institute of the Kola Science Center, RAS; Apatity Russia
2. Space Research Institute, RAS; Moscow Russia
3. Institute of Applied Physics, RAS; Nizhny Novgorod Russia
4. Sodankylä Geophysical Observatory; Sodankylä Finland
5. Institute of Atmospheric Physics, ASCR; Prague Czech Republic
6. Faculty of Mathematics and Physics; Charles University; Prague Czech Republic
7. Department of Physics and Astronomy; University of Iowa; Iowa City Iowa USA
8. Los Alamos National Laboratory; Los Alamos New Mexico USA