Bianchi, C., L. Ciraolo, and C. Scotto. “Low Ionospheric Observations by Means of the Software Receiver for Omega Signal”. Annals of Geophysics 37, no. 1 (April 18, 1994). Accessed April 27, 2024. https://www.annalsofgeophysics.eu/index.php/annals/article/view/4237.