PORTER MICHAEL E. (1980). COMPETITIVE STRATEGY: TECHNIQUES FOR ANALYSING ...COMPETITORS. FREE PRESS.
Chicago-čujuhus (17. p.)PORTER MICHAEL E. COMPETITIVE STRATEGY: TECHNIQUES FOR ANALYSING ...COMPETITORS. NEW YORK LONDON: FREE PRESS, 1980.
MLA-čujuhus (9. p.)PORTER MICHAEL E. COMPETITIVE STRATEGY: TECHNIQUES FOR ANALYSING ...COMPETITORS. FREE PRESS, 1980.
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