Porter, M. (1985). Competitive advantage. Free press.
Lua i Stíl Chicago (17ú heag.)Porter, Michael. Competitive Advantage. New york: Free press, 1985.
Lua MLA (9ú heag.)Porter, Michael. Competitive Advantage. Free press, 1985.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.