Department of Physics and Astronomy, George Mason University Fairfax, Fairfax, VA, United States NASA Goddard Space Flight Center, Greenbelt, MD, United States
Univ Massachusetts Lowell, Lowell, MA, United States
Lowell Digisonde International, Lowell, MA, United States
Lowell Digisonde International, Lowell, MA, United States
Institute of Solar-Terrestrial Physics SB RAS, Irkutsk, Russia