Olensia, Y., & Kurnia Sari, R. (2017). POTRET CAMBRIDGE ADVANCED (CHEMISTRY AS AND A LEVEL) DI SEKOLAH MUTIARA HARAPAN RIAU TAHUN AJARAN 2015/2016. Orbital: Jurnal Pendidikan Kimia, 1(1), 12-21. https://doi.org/10.19109/ojpk.v1i1.1861