MAGNETIC RESULTS SODANKYLAE 1978 = RESULTATS D'OBSERVATIONS MAGNETIQUES SODANKYLAE 1978KATAJA E.1979; VERAEFF. GEOPHYS. OBS. FINN. AKAD. WISS.; ISSN 0355-0826; FIN; DA. 1979; NO 64; 32 P.Serial Issue

IMF POLARITY AND ANNUAL VARIATIONS OF THE DST INDEXOKSMAN J; KATAJA E.1981; GEOPHYS. J. R. ASTRON. SOC.; ISSN 0016-8009; GBR; DA. 1981; VOL. 65; NO 3; PP. 603-609; BIBL. 20 REF.Article

An extension of the geomagnetic activity index series aa for two solar cycles (1844-1868)NEVANLINNA, H; KATAJA, E.Geophysical research letters. 1993, Vol 20, Num 23, pp 2703-2706, issn 0094-8276Article

Hemispheric asymmetry of the sun suggested by the annual variation of the aa indexOKSMAN, J; KATAJA, E.Annales geophysicae. Series A. Upper atmosphere and space sciences. 1986, Vol 4, Num 1, pp 69-73Article

BERICHT UEBER DIE TAETIGKEIT DES OBSERVATORIUMSKOMITEES UND DES GEOPHYSIKALISCHEN OBSERVATORIUMS ZU SODANKYLAE IM JAHRE 1965 (ACTIVITIES OF THE OBSERVATORY COMMITTEE AND GEOPHYSICAL OBSERVATORY OF THE FINNISH ACADEMY OF SCIENCE, 1965).VAEISAELAE V; MATTILA P; KATAJA E et al.1969; SITZUNGSBER. FINN. AKAD. WISS; FIN; 1969, VOL. 1966, P. 35 A 56Miscellaneous

VARIATIONS IN PC 1 FREQUENCY WITH LATITUDE.HEACOCK RR; HESSLER VP; SUCKSDORFF C et al.1968; NATURE.; 1968(1), VOL. 217, NUM. 5124, P. 153 A 155Miscellaneous