TY - JOUR A1 - Feichter, E. A1 - Leitinger, R. T1 - A 22-year cycle in the F layer ionization of the ionosphere JO - Ann. Geophys. J1 - ANGEO VL - 15 IS - 8 SP - 1015 EP - 1027 Y1 - 1997/08/31 PB - Springer Verlag SN - 1432-0576 UR - https://angeo.copernicus.org/articles/15/1015/1997/ L1 - https://angeo.copernicus.org/articles/15/1015/1997/angeo-15-1015-1997.pdf DO - 10.1007/s00585-997-1015-0 ER -