Ngoc, Doan, Thi Huyen Trang, Hoang, Cong Hoan, Tran, Van Sang, Nguyen, AND Minh Chau, Nguyen. " The Value of Ultrasound in Classification of Thyroid Hypoechoic Nodules" VNU Journal of Science: Medical and Pharmaceutical Sciences [Online], Volume 37 Number 3 (21 September 2021)