Sari, Dwy Puspita, et al. “VALIDITY AND PRACTICALITY OF STEM-PBL BASED THERMOCHEMISTRY TEACHING MATERIALS FOR CHEMISTRY EDUCATION STUDENTS”. JPPIPA (Jurnal Penelitian Pendidikan IPA), vol. 11, no. 1, June 2026, pp. 79-85, doi:10.26740/jppipa.v11n1.p79-85.