Adaniyah, R. 2017. The Implementation of Quiz-Demonstration-Practice-Revision (QDPR) Learning Model to Improve University Students’ Knowledge of English Pronunciation and Their Ability to Pronounce English Central Vowel /ᴧ/ and English Back Vowel /αː/. Voices of English Language Education Society. 1, 2 (Sep. 2017). DOI:https://doi.org/10.29408/veles.v1i2.425.