Fisher, R. (1991). Getting to Yes. Random House Business.
Dyfyniad Arddull ChicagoFisher, Roger. Getting to Yes. London: Random House Business, 1991.
Dyfyniad MLAFisher, Roger. Getting to Yes. Random House Business, 1991.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.