Cita APA

Drucker, P. F. (1957). America's next twenty years. New York: Happer and Brother.

Citación estilo Chicago

Drucker, Peter F. America's Next Twenty Years. New York: Happer and Brother, 1957.

Cita MLA

Drucker, Peter F. America's Next Twenty Years. New York: Happer and Brother, 1957.