TY - JOUR A1 - Mielich, J. A1 - Bremer, J. T1 - A modified index for the description of the ionospheric short- and long-term activity JO - Ann. Geophys. J1 - ANGEO VL - 28 IS - 12 SP - 2227 EP - 2236 Y1 - 2010/12/21 PB - Copernicus Publications SN - 1432-0576 UR - https://angeo.copernicus.org/articles/28/2227/2010/ L1 - https://angeo.copernicus.org/articles/28/2227/2010/angeo-28-2227-2010.pdf DO - 10.5194/angeo-28-2227-2010 ER -