Drucker, P. F. (1957). America's next twenty years. New York: Happer and Brother.
Stile di citazione ChicagoDrucker, Peter F. America's Next Twenty Years. New York: Happer and Brother, 1957.
Citazione MLADrucker, Peter F. America's Next Twenty Years. New York: Happer and Brother, 1957.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.