Trần;Thị Thu Hiền, & Phan Văn Hòa. (2015). An investigation into the errors in pronouncing english long and short vowels of english- majored juniors in university of da nang- university of foreign language studies. ĐHĐN: ĐHĐN.

Trần;Thị Thu Hiền, و Phan Văn Hòa. An Investigation Into the Errors in Pronouncing English Long and Short Vowels of English- Majored Juniors in University of Da Nang- University of Foreign Language Studies. ĐHĐN: ĐHĐN, 2015.

Trần;Thị Thu Hiền, و Phan Văn Hòa. An Investigation Into the Errors in Pronouncing English Long and Short Vowels of English- Majored Juniors in University of Da Nang- University of Foreign Language Studies. ĐHĐN: ĐHĐN, 2015.