SCHWARTZ, D. J. (1981). Marketing Today A Basic Approach Third Edition/ David J. Schwarts. Harcourt Brace Jovanovic, Inc.
Lua i Stíl Chicago (17ú heag.)SCHWARTZ, David J. Marketing Today A Basic Approach Third Edition/ David J. Schwarts. Harcourt Brace Jovanovic, Inc, 1981.
Lua MLA (8ú heag.)SCHWARTZ, David J. Marketing Today A Basic Approach Third Edition/ David J. Schwarts. Harcourt Brace Jovanovic, Inc, 1981.
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