Sirichai Duangngoen และ Wanchai Arunpraparut;Piyapong Tongdeenok. (2021) Watershed Classification in an Unclassified Area to Analyze Landform Using Geographic Information System and Various Digital Elevation Models. <i>Thai Journal of Forestry</i>, <i>40</i>(1), 108-122.Sirichai Duangngoen และ Wanchai Arunpraparut;Piyapong Tongdeenok. "Watershed Classification in an Unclassified Area to Analyze Landform Using Geographic Information System and Various Digital Elevation Models". Thai Journal of Forestry 40 (2021):108-122.Sirichai Duangngoen และ Wanchai Arunpraparut;Piyapong Tongdeenok. Watershed Classification in an Unclassified Area to Analyze Landform Using Geographic Information System and Various Digital Elevation Models. Kasetsart University:ม.ป.ท. 2021.