1. Faculty of Mathematics and Computer Science, University of Science, Ho Chi Minh City, Ho Chi Minh City, Vietnam + Vietnam National University, Ho Chi Minh City, Vietnam + Faculty of Fundamental sciences, Ho Chi Minh City Universty of Food Industry, Tay Thanh Ward, Ho Chi Minh City, Vietnam
2. Ho Chi Minh City University of Foreign Languages-Information Technology, Su Van Hanh, Ho Chi Minh City, Vietnam
3. University of Khanh Hoa, Nha Trang City, Vietnam
4. Faculty of Mathematics and Computer Science, University of Science, Ho Chi Minh City, Vietnam, Ho Chi Minh City, Vietnam + Vietnam National University, Ho Chi Minh City, Vietnam