Fatimah, H. et al. 2023. The Validity and Readability Test for the Development of PBL-Based UKBM Teaching Materials on the Physics of the Human Circulatory System is Oriented Towards Students’ Critical Thinking . Jurnal Penelitian Pendidikan IPA. 9, 1 (Jan. 2023), 9–12. DOI:https://doi.org/10.29303/jppipa.v9i1.1496.