TOZZI, R.; DE SANTIS, A. Detecting geomagnetic field nonlinearities by bispectral analysis and a phase coupling nonlinear technique. Annals of Geophysics, [S. l.], v. 45, n. 2, 2002. DOI: 10.4401/ag-3514. Disponível em: https://www.annalsofgeophysics.eu/index.php/annals/article/view/3514. Acesso em: 23 may. 2022.