Syifaiyah, R., Tukiran, T., & Erman, E. (2018). DEVELOPMENT OF CHEMISTRY INSTRUCTION MATERIAL USING PROBLEM BASED LEARNING MODEL FOR INCREASING THE STUDENT OF SENIOR HIGH SCHOOL LEARNING ACHIEVEMENT. JPPS (Jurnal Penelitian Pendidikan Sains), 7(2), 1479–1486. https://doi.org/10.26740/jpps.v7n2.p1479-1486