Porter Michael E. (1980). Competitve Strategy: Techniques for Analyzing Industries and Competitors. Free Press.
Chicago Style aipamenaPorter Michael E. Competitve Strategy: Techniques for Analyzing Industries and Competitors. New York: Free Press, 1980.
MLA aipamenaPorter Michael E. Competitve Strategy: Techniques for Analyzing Industries and Competitors. Free Press, 1980.
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