George M. Heinzman came across the personal accounts of the participants in the Battle of Beecher Island while doing research for his historical novel, Only the Earth and the Mountains , which was published by Macmillan in 1964.
For further reading: The Long Death, by Ralph K. Andrist (Macmillan, 1964); The Compact History of the Indian Wars , by john Tebbel (Hawthorn, 1966).