APA (7th ed.) Citation

Cather, W. (1942). My mortal enemy (7. print.). Knopf.

Chicago Style (17th ed.) Citation

Cather, Willa. My Mortal Enemy. 7. print. New York: Knopf, 1942.

MLA (9th ed.) Citation

Cather, Willa. My Mortal Enemy. 7. print. Knopf, 1942.