Wibowo, A. I. ., Adi, W. T. . and Pratama, R. M. D. . (2021) “Mispronouncing English Vowel Sounds on Office Admisintrative’s Students Universitas Bina Sarana Informatika”, IJOLTL (Indonesian Journal of Language Teaching and Linguistics), 6(3), pp. 231–238. doi: 10.30957/ijoltl.v6i3.679.