T. Srichan and P. Tangsupphathawat, “On the distribution of primitive roots that are $(k,r)$-integers”, Armen.J.Math., vol. 11, no. 12, pp. 1–12, Dec. 2019, Accessed: May 09, 2026. [Online]. Available: http://test.armjmath.sci.am/index.php/ajm/article/view/298