AGIZEW, K. T.; USHACHEW, E. G.; HURISA, S. S.; GIZAW, D. T. Constraints of Students’ Mathematical Problem Solving and Proving Skill Competences, the Case of Four preparatory Schools in Guraghe Zone. International Journal of Sciences: Basic and Applied Research (IJSBAR), [S. l.], v. 40, n. 2, p. 18–29, 2018. Disponível em: https://www.gssrr.org/index.php/JournalOfBasicAndApplied/article/view/8956. Acesso em: 6 may. 2024.