ONDRÁŠKOVÁ, Adriena; ŠEVČÍK, Sebastián; KOSTECKÝ, Pavel. A significant decrease of the fundamental Schumann resonance frequency during the solar cycle minimum of 2008-9 as observed at Modra Observatory. Contributions to Geophysics and Geodesy, [S. l.], v. 39, n. 4, p. 345–354, 2009. DOI: 10.2478/v10126-009-0013-5. Disponível em: https://journal.geo.sav.sk/cgg/article/view/24. Acesso em: 13 aug. 2025.