Thabit, Samar Abdalkaream, Loay E. George, and Khalid A. Hadi. 2020. “Seasonal Variations of the Optimum Reliable Frequencies During Maximum and Minimum Periods of Solar Cycle 24”. Al-Mustansiriyah Journal of Science 31 (4): 15-27. https://doi.org/10.23851/mjs.v31i4.887.