OLIVEIRA WERNECK DE CARVALHO, VINICIUS JOSE (Observatorio NacionalDivisão de Programas de Pós-Graduação - DIPPGBrasilONPrograma de Pós-Graduação em Geofísica, 2014-04-30)
The Earth's magnetic field shows variations covering a relatively large range in period / frequency. Changes in external source are short and may be on the order of fractions of seconds, while the variation over time and ...