Hamidiyah, A., B. K. Purwo, and F. Sari. “Production of the English Voiceless Labiodental Fricative /f/ By Sundanese EFL Student Teachers: A Case Study”. Journal La Edusci, Vol. 7, no. 4, July 2026, pp. 1084-99, https://newinera.com/index.php/JournalLaEdusci/article/view/5108.