NASH, E. L. (1982). Direct Marketing Strategy, Planning, Execution Edward L. Nash. McGraw-Hill.
Lua i Stíl Chicago (17ú heag.)NASH, Edward L. Direct Marketing Strategy, Planning, Execution Edward L. Nash. McGraw-Hill, 1982.
Lua MLA (8ú heag.)NASH, Edward L. Direct Marketing Strategy, Planning, Execution Edward L. Nash. McGraw-Hill, 1982.
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