PORTER MICHAEL E. (1998). ON COMPETITION. HARVERD BUSINESS SCHOOL.
Čikaški stil citiranja (17. izdanje)PORTER MICHAEL E. ON COMPETITION. BOSTON: HARVERD BUSINESS SCHOOL, 1998.
MLA način citiranja (9. izdanje)PORTER MICHAEL E. ON COMPETITION. HARVERD BUSINESS SCHOOL, 1998.
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