U.S. Geological Survey. National Hydrography Dataset high-resolution flowline data. The National Map互联网档案馆的存檔,存档日期March 29, 2012,., accessed April 26, 2011
U.S. Geological Survey. National Hydrography Dataset high-resolution flowline data. The National Map互联网档案馆的存檔,存档日期March 29, 2012,., accessed April 26, 2011