Cohen, W. A. (2013). Drucker on marketing: Lessons from the world's most influential business thinker. McGraw-Hill.
Lua i Stíl Chicago (17ú heag.)Cohen, William A. Drucker on Marketing: Lessons from the World's Most Influential Business Thinker. New York: McGraw-Hill, 2013.
Lua MLA (8ú heag.)Cohen, William A. Drucker on Marketing: Lessons from the World's Most Influential Business Thinker. McGraw-Hill, 2013.
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