Bencze, P., Buresová, D., Lastovicka, J., & Märcz, F. (2004). Behaviour of the F1-region, and Esand spread-F phenomena at European middle latitudes, particularly under geomagnetic storm conditions. Annals of Geophysics, 47(2-3 Sup.). https://doi.org/10.4401/ag-3290