Cohen, W. A. 1. (1998). The marketing plan (2nd ed.). New York ; Chichester: John Wiley and Sons.
Dyfyniad Arddull ChicagoCohen, William A. 1937-. The Marketing Plan. 2nd ed. New York ; Chichester: John Wiley and Sons, 1998.
Dyfyniad MLACohen, William A. 1937-. The Marketing Plan. 2nd ed. New York ; Chichester: John Wiley and Sons, 1998.
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