APA-viite (7. p.)

PORTER MICHAEL E. (1980). COMPETITIVE STRATEGY: TECHNIQUES FOR ANALYZING INDUSTRIES AND COMPETITORS. FREE PRESS.

Chicago-viite (17. p.)

PORTER MICHAEL E. COMPETITIVE STRATEGY: TECHNIQUES FOR ANALYZING INDUSTRIES AND COMPETITORS. NEW YORK: FREE PRESS, 1980.

MLA-viite (9. p.)

PORTER MICHAEL E. COMPETITIVE STRATEGY: TECHNIQUES FOR ANALYZING INDUSTRIES AND COMPETITORS. FREE PRESS, 1980.