Indians of the U.S. hearings before the United States House Committee on Indian Affairs, Sixty-Sixth Congress, second session, on May 10-14, 16-23, 25, 26, 29, 30, June 1, 3, 1920. Vol. 3, Investigation of the Field Service :

Hearings were held, May 10-14 in Oklahoma; May 16-18 in New Mexico; May 18-23, 25 in Arizona; May 26 in Riverside, Calif.; May 29 in Salt Lake City, Utah; May 30 at Fort Hall, Idaho; and June 1 and 3 in Montana.