Le Khac Dong และผู้แต่งคนอื่นๆ. (2019) Application tool of the Global Positioning System as the first stage of patrol skills to support protected areas. <i>Songklanakarin Journal of Science and Technology</i>, <i>41</i>(4), 747-754.Le Khac Dong และผู้แต่งคนอื่นๆ. "Application tool of the Global Positioning System as the first stage of patrol skills to support protected areas". Songklanakarin Journal of Science and Technology 41 (2019):747-754.Le Khac Dong และผู้แต่งคนอื่นๆ. Application tool of the Global Positioning System as the first stage of patrol skills to support protected areas. Research and Development Office, Prince of Songkla University:ม.ป.ท. 2019.