binti Anuar, A. A. ., and N. . Kama. “The Suitable Symbol for Arabic Phoneme (‘Ayn) in Roman Writing System: Arabic Phoneme”. Al-Ḍād Journal, vol. 5, no. 1, Nov. 2021, pp. 39-52, https://vmis.um.edu.my/index.php/aldaad/article/view/33462.