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Dyfyniad Arddull ChicagoRies, AI. The 22 Immutable Laws of Marketing. New delhi: Harper Collins Publications, 1996.
Dyfyniad MLARies, AI. The 22 Immutable Laws of Marketing. Harper Collins Publications, 1996.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.