Shell, G. R. (2006). Bargaining for Advantage (2nd.). Penguin.
Dyfyniad Arddull ChicagoShell, G. Richard. Bargaining for Advantage. 2nd. New York: Penguin, 2006.
Dyfyniad MLAShell, G. Richard. Bargaining for Advantage. 2nd. Penguin, 2006.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.