Tong Thi Hao Tam; Pham Thao; Ha Lam Tung; Cao Thi Thu Huong; Tong Thi Minh Ngoc; Pham Minh Hoan. RESEARCH AND APPLY AUTOMATIC SENDING MESSAGE SYSTEM GCM ON THE INTERNAL INFORMATION WEBSITE OF NATIONAL ECONOMICS UNIVERSITY. jst 2017, 15, 76-81.