Miner and Unrau, End of Indian Kansas, 121-132.
Gates, Fifty Million Acres, 194-229.
Francis Paul Prucha, The Great Father: The United States Government and the American Indians, 2 vols. (Lincoln: Univ. of Nebraska Press, 1984), 1:527-33.
Duane Swanson, The Northern Pacific Railroad and the Sisseton-Wahpeton Sioux: A Case in Land Acquisition (M.A. thesis, Univ. of Delaware, 1972), 24, 27, 29, 31, 33-36.
Whether Cowen was paid is uncertain, but negotiations moved forward.
See Duane Swanson, The Northern Pacific Railroad and the Sisseton-Wahpeton Sioux: A Case in Land Acquisition (M.A. thesis, Univ. of Delaware, 1972), 41, 43-44, 48-54.
George Becker and James Smith Jr. to Cooke, Sept. 5, 1872,; Jay Cooke to Brother Harry, May 24, 1872; Cooke to Cass, March 17, 1873, Cooke to B. F. Wade, March 22, 1873, Cooke to Maj. Benj. Thompson, March 22, 1873, LBs, all in Cooke Papers.
Swanson, Northern Pacific Railroad, 6164.
Cooke to Professor Carey (?), March 10, 1873, Cooke to Bro. Harry, March 14, 1873, LBs, Cooke Papers.