Maulana, Muhammmad Irham, et al. “A Content-Based Supplementary Book Development for Islamic Junior High School”. Journal of English Teaching and Linguistic Issues (JETLI), vol. 4, no. 1, Mar. 2025, pp. 34-43, https://ejournal.iaingorontalo.ac.id/index.php/JETLI/article/view/2055.