THABIT, Samar Abdalkaream; GEORGE, Loay E.; HADI, Khalid A. Seasonal Variations of the Optimum Reliable Frequencies During Maximum and Minimum Periods of Solar Cycle 24. Al-Mustansiriyah Journal of Science, Baghdad, Iraq, v. 31, n. 4, p. 15–27, 2020. DOI: 10.23851/mjs.v31i4.887. Disponível em: https://mjs.uomustansiriyah.edu.iq/index.php/MJS/article/view/887.. Acesso em: 19 may. 2024.