James, E. 1822. Account of an Expedition from Pittsburgh to the Rocky Mountains: Performed in the Years 1819 and '20, by Order of the Hon. J. C. Calhoun, Sec'y of War; Under the Command of Major Stephen H. Long/ From the Notes of Major Long, Mr. T. Say, and Other Gentlemen of the Exploring Party. Volume 1.  Philadelphia: H.C. Carey and I. Lea.