Exercise Motivation among Fitness Center Members: A Combined Qualitative and Q-Sorting Approach oleh Truong Thanh Nam, Charuai Suwanbamrung, Omid Dadras, Xiang-Yu Hou, Doan Hoang Phu, Pham Trung Tin, Huynh Khai Quang, Thai Thi Ngoc Thuy, Temesgen A. Ageru, Saifon Aekwarankoon, Sang-arun Isaramalai, Cua Ngoc Le