APA (7th ed.) Citation

Powys, J. C. (1922). One hundred best books, with commentary and an essay on Books and reading. American library service.

Chicago Style (17th ed.) Citation

Powys, John Cowper. One Hundred Best Books, with Commentary and an Essay on Books and Reading. New York: American library service, 1922.

MLA (9th ed.) Citation

Powys, John Cowper. One Hundred Best Books, with Commentary and an Essay on Books and Reading. American library service, 1922.