HEJDA, P.; HORÁČEK, J.; BAYER, T. Secular variation on the territory of the Czech Republic and reduction of the magnetic survey to the epoch 2010.5. Annals of Geophysics, [S. l.], v. 55, n. 6, 2013. DOI: 10.4401/ag-5445. Disponível em: https://www.annalsofgeophysics.eu/index.php/annals/article/view/5445. Acesso em: 2 dec. 2021.