Prowoto, Joko, Gusdi Sastra, and Amel Yanis. “Phonological Disorders of Children With Down Syndrome Based on the Level of Intelligence: A Case Study”. OKARA: Jurnal Bahasa dan Sastra 13, no. 1 (May 31, 2019): 81–92. Accessed July 31, 2026. https://siakaddev.iainmadura.ac.id/index.php/okara/article/view/2276.