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Curtis, Sam'l P. "The Army of the South-West, and the First Campaign in Arkansas. Chapter Sixth: Reports of Col. Osterhaus and General Asboth, 1st and 2nd Divisions." The Annals of Iowa 1867 (1867), 823-833.
Available at: http://ir.uiowa.edu/annals-of-iowa/vol1867/iss2/4