H. Al-Shamma, Salim, سالم, Muzahim I. Azawi, and مزاحم. 2013. “A Suitable Analytical Formula for the K Shell Ionization Cross Section of Carbon and Potassium Atoms by Electron Impact”. Journal of Education and Science (JES) 26 (3):18-22. https://doi.org/10.33899/edusj.2013.89914.