Sinaga, P., Suhandi, A., & Liliasari, . (2014). Improving the Ability of Writing Teaching Materials and Self-Regulation of Pre-Service Physics Teachers through Representational Approach. International Journal of Sciences: Basic and Applied Research (IJSBAR), 15(1), 80–94. Retrieved from https://gssrr.org/index.php/JournalOfBasicAndApplied/article/view/2084