Ellen Guffey, M. (2006). Business communicationProcess productMary Ellen Guffey, Kathleen Rhodes dan Patricia Rogin. Salemba Empat.
Dyfyniad Arddull ChicagoEllen Guffey, Mary. Business CommunicationProcess ProductMary Ellen Guffey, Kathleen Rhodes Dan Patricia Rogin. Salemba Empat, 2006.
Dyfyniad MLAEllen Guffey, Mary. Business CommunicationProcess ProductMary Ellen Guffey, Kathleen Rhodes Dan Patricia Rogin. Salemba Empat, 2006.
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