Poctor, T., & Day, G. S. Marketing research.
Dyfyniad Arddull ChicagoPoctor, Tony, and George S. Day. Marketing Research.
Dyfyniad MLAPoctor, Tony, and George S. Day. Marketing Research.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.