Rizqi , N. R. ., & Arini , L. . (2020). The Developing of Teaching Materials Oriented to Problem-Based Learning to Improve Students’ Mathematical Communication Ability. International Journal of Sciences: Basic and Applied Research (IJSBAR), 54(4), 186–195. Retrieved from https://gssrr.org/index.php/JournalOfBasicAndApplied/article/view/11899