RINTIA, R.; SYLVIA, I. Validitas Lembar Kerja Peserta Didik (LKPD) Sosiologi Menggunakan Model Problem Based Learning (PBL) Materi Perubahan Sosial. Naradidik: Journal of Education and Pedagogy, v. 3, n. 2, p. 116-125, 14 Jun. 2024.