Ratna Sari Dewi, Desi Nahartini, Dede Puji Setiono, Febria Afia Rahmah, Fahrurrozi, Apri Wahyudi. 2020. “Exploring Materials Development of English Curriculum in Indonesia: A Content Analysis Study”. International Journal of Advanced Science and Technology 29 (06), 1475 -82. http://sersc.org/journals/index.php/IJAST/article/view/11884.