We express our big thanks to the people listed below. They have been of tremendous help by communicating to us their pictures and videos.

• Nguyen Manh Khuong
• Pham Dinh Thuan
• Tran Ton Dan
• Hoang Dinh Truyen
• Pham Minh Vuong
• Pham Duc Kinh
• Tran Thi Can
• Nguyen Huong Thuy
• Do Tuan Viet
• Pham Thu Phong