Symons, T. W., & Downing, A. (1882). Report of an examination of the upper Columbia River and the territory in its vicinity in September and October, 1881: To determine its navigability, and adaptability to steamboat transportation. G.P.O..
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Symons, T. W., و Alfred Downing. Report of an Examination of the Upper Columbia River and the Territory in Its Vicinity in September and October, 1881: To Determine Its Navigability, and Adaptability to Steamboat Transportation. Washington [D.C.]: G.P.O., 1882.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Symons, T. W., و Alfred Downing. Report of an Examination of the Upper Columbia River and the Territory in Its Vicinity in September and October, 1881: To Determine Its Navigability, and Adaptability to Steamboat Transportation. G.P.O., 1882.