Yani, Maulinda, et al. “Application of Contextual Teaching and Learning (CTL) Learning Strategies on Metacognitive Ability and Leaarning Outcomes in Immune System Materials”. Jurnal Penelitian Pendidikan IPA, vol. 7, no. 4, Oct. 2021, pp. 576-81, doi:10.29303/jppipa.v7i4.765.