SHALTOUT, M. A. M. ., and M. T. Y. . TADROS. “Variations of the Solar Activity and Irradiance, and Their Influence on the Flooding of the River Nile”. MAUSAM, vol. 41, no. 3, July 1990, pp. 53-62, doi:10.54302/mausam.v41i3.2722.