Mardiah, A., M. Ikhsan, and M. Marwan. “Improving Students’ Mathematical Reasoning Ability Through Problem Posing Approaches at SMPN 19 Banda Aceh”. International Journal of Sciences: Basic and Applied Research (IJSBAR), vol. 44, no. 2, Mar. 2019, pp. 26-36, https://www.gssrr.org/index.php/JournalOfBasicAndApplied/article/view/9790.