Safitri, Linda, et al. “Integrating Problem-Based Learning into E-Modules : A Development Study With Validation and Student Response Analysis”. Jurnal Kependidikan: Jurnal Hasil Penelitian Dan Kajian Kepustakaan Di Bidang Pendidikan, Pengajaran Dan Pembelajaran, vol. 11, no. 1, Mar. 2025, pp. 397-09, doi:10.33394/jk.v11i1.14836.