PORTER MICHAEL E. (1998). COMPETITIVE STRATEGY: TECHNIQUES FOR ANALYZING INDU AND COMPETITORS. FREE PRESS.
Chicago-čujuhus (17. p.)PORTER MICHAEL E. COMPETITIVE STRATEGY: TECHNIQUES FOR ANALYZING INDU AND COMPETITORS. NEW YORK: FREE PRESS, 1998.
MLA-čujuhus (9. p.)PORTER MICHAEL E. COMPETITIVE STRATEGY: TECHNIQUES FOR ANALYZING INDU AND COMPETITORS. FREE PRESS, 1998.
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