Ries Al. (2004). Origin of Brands. Harper Collins.
Dyfyniad Arddull ChicagoRies Al. Origin of Brands. New York: Harper Collins, 2004.
Dyfyniad MLARies Al. Origin of Brands. Harper Collins, 2004.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.