Ries, A. (1993). Las 22 leyes inmutables del marketing. Mc Graw Hill.
Chicago Style (17th ed.) CitationRies, Al. Las 22 Leyes Inmutables Del Marketing. Mc Graw Hill, 1993.
MLA (9th ed.) CitationRies, Al. Las 22 Leyes Inmutables Del Marketing. Mc Graw Hill, 1993.
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