Cita APA (7a ed.)

Llewellyn, R. (1940). How Green was my Valley. Pocket books.

Cita Chicago Style (17a ed.)

Llewellyn, Richard. How Green Was My Valley. New York: Pocket books, 1940.

Cita MLA (9a ed.)

Llewellyn, Richard. How Green Was My Valley. Pocket books, 1940.