APA (7th ed.) Citation

Duncan, K., & Nickols, D. F. (1944). Mentor Graham: The man who taught Lincoln. University of Chicago Press.

Chicago Style (17th ed.) Citation

Duncan, Kunigunde, and D. F. Nickols. Mentor Graham: The Man Who Taught Lincoln. Chicago: University of Chicago Press, 1944.

MLA (9th ed.) Citation

Duncan, Kunigunde, and D. F. Nickols. Mentor Graham: The Man Who Taught Lincoln. University of Chicago Press, 1944.