SUMARUK, Y.; REDA, J. Secular variations of the geomagnetic field and solar activity. Geofizicheskiy Zhurnal, [S. l.], v. 33, n. 4, p. 134–141, 2011. DOI: 10.24028/gzh.0203-3100.v33i4.2011.116902. Disponível em: https://journals.uran.ua/geofizicheskiy/article/view/116902. Acesso em: 3 mar. 2024.