1. Polar Geophysical Institute Apatity Russia
2. Institute of Applied PhysicsRAS Nizhny Novgorod Russia
3. Space Research InstituteRAS Moscow Russia
4. Sodankylä Geophysical Observatory Sodankylä Finland
5. Department of Space Physics, Institute of Atmospheric Physics of the Czech Academy of Sciences Prague Czechia
6. Faculty of Mathematics and PhysicsCharles University Prague Czechia