Chernogor, L. F., Garmash, K. P., Zhdanko, Y. H., Leus, S. G., & Podnos, V. A. (2020). Software and hardware system of multi-frequency oblique sounding the ionosphere. Visnyk of V.N. Karazin Kharkiv National University, Series “Radio Physics and Electronics”, (33), 42-59. https://doi.org/10.26565/2311-0872-2020-33-04