APA (7th ed.) Citation

Janet, P., Guthrie, H. M., & Guthrie, E. R. (1924). Principles of psychotherapy. The MacMillan Company.

Chicago Style (17th ed.) Citation

Janet, Pierre, Helen MacDonald‏ Guthrie, and Edwin R. Guthrie. Principles of Psychotherapy. New York: The MacMillan Company, 1924.

MLA (9th ed.) Citation

Janet, Pierre, et al. Principles of Psychotherapy. The MacMillan Company, 1924.