Willamette River. Geographic Names Information System. U.S. Geological Survey. November 28, 1980 [June 25, 2010]. (原始内容存档于2023-11-04). Source and mouth elevation derived from Google Earth search using GNIS source and mouth coordinates.
oregonencyclopedia.org
Robbins, William G. Willamette River. The Oregon Encyclopedia. Portland State University and the Oregon Historical Society. [May 19, 2014]. (原始内容存档于2020-12-04).
web.archive.org
Willamette River. Geographic Names Information System. U.S. Geological Survey. November 28, 1980 [June 25, 2010]. (原始内容存档于2023-11-04). Source and mouth elevation derived from Google Earth search using GNIS source and mouth coordinates.
Robbins, William G. Willamette River. The Oregon Encyclopedia. Portland State University and the Oregon Historical Society. [May 19, 2014]. (原始内容存档于2020-12-04).