APA (7th ed.) Citation

OPEC. (2018). Annual statistical bulletin. Organization of the Petroleum Exporting Countries.

Chicago Style (17th ed.) Citation

OPEC. Annual Statistical Bulletin. Vienna: Organization of the Petroleum Exporting Countries, 2018.

MLA (9th ed.) Citation

OPEC. Annual Statistical Bulletin. Organization of the Petroleum Exporting Countries, 2018.

Warning: These citations may not always be 100% accurate.