Yana, Selviyana, et al. “Application of Problem Based Learning (PBL) Model to Improve Problem Solving Skill from Critical Thinking Skill Students on Dynamic Fluid Materials”. Jurnal Penelitian Pendidikan IPA, vol. 8, no. 2, Apr. 2022, pp. 521-7, doi:10.29303/jppipa.v8i2.1329.