Porter, M. (2004). Competitive Advantage (1st.). Free Press.
Lua i Stíl Chicago (17ú heag.)Porter, Michael. Competitive Advantage. 1st. Free Press, 2004.
Lua MLA (9ú heag.)Porter, Michael. Competitive Advantage. 1st. Free Press, 2004.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.