Supriyadi, Supriyadi. “Quality of Bahasa Indonesia Textbooks Used in Junior High School”. Jurnal Kependidikan: Penelitian Inovasi Pembelajaran 2, no. 1 (May 30, 2018): 39–55. Accessed May 17, 2025. https://journal.uny.ac.id/index.php/jk/article/view/10122.