APA (7th ed.) Citation

Hafen, L. R. (1970). Colorado: The story of a western commonwealth. AMS Press.

Chicago Style (17th ed.) Citation

Hafen, LeRoy R. Colorado: The Story of a Western Commonwealth. New York: AMS Press, 1970.

MLA (9th ed.) Citation

Hafen, LeRoy R. Colorado: The Story of a Western Commonwealth. AMS Press, 1970.