K. T. Agizew and S. S. Hurisa, “Research Based Mathematics Problem Solving and Proving skills Competences”, IJSBAR, vol. 42, no. 4, pp. 189–202, Dec. 2018, Accessed: Oct. 12, 2025. [Online]. Available: https://www.gssrr.org/JournalOfBasicAndApplied/article/view/9368