APA (7th ed.) Zitazioa
Van Vactor, S. (2010). Introduction to the global oil & gas business. PennWell Corp..
Chicago Style (17th ed.) Zitazioa
Van Vactor, Samuel. Introduction to the Global Oil & Gas Business. Tulsa, Okla.: PennWell Corp., 2010.
MLA (9th ed.) Zitazioa
Van Vactor, Samuel. Introduction to the Global Oil & Gas Business. PennWell Corp., 2010.
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