Fuadi, H. et al. 2022. Feasibility of PBL (Problem Based Learning)-based Sound Wave Electronic Student Worksheet for High School Students Using the Liveworksheet Application. Jurnal Penelitian Pendidikan IPA. 8, 4 (Oct. 2022), 1961–1971. DOI:https://doi.org/10.29303/jppipa.v8i4.1982.