Cohen, W. A. (1984). Direct response marketing: An enterprencurial approach. john wiley& sons.
Čikaški stil citiranjaCohen, William A. Direct Response Marketing: An Enterprencurial Approach. New York: john wiley& sons, 1984.
MLA način citiranjaCohen, William A. Direct Response Marketing: An Enterprencurial Approach. john wiley& sons, 1984.
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