Pilipenko, V. A., and E. N. Fedorov. “Magnetotelluric Sounding of the Crust and Hydromagnetic Monitoring of the Magnetosphere With the Use of ULF Waves”. Annals of Geophysics 36, no. 5-6 (November 25, 1993). Accessed April 26, 2024. https://www.annalsofgeophysics.eu/index.php/annals/article/view/4243.