Cita APA (7a ed.)

Grace, R. (2007). Oil: An overview of the petroleum industry (6th ed.). Gulf Pub. Co..

Cita Chicago Style (17a ed.)

Grace, Robert. Oil: An Overview of the Petroleum Industry. 6th ed. Houston, Tex.: Gulf Pub. Co., 2007.

Cita MLA (8a ed.)

Grace, Robert. Oil: An Overview of the Petroleum Industry. 6th ed. Gulf Pub. Co., 2007.