↑ “OPEC Statute” (PDF). Organization of the Petroleum Exporting Countries. 2008. tr. 8. Truy cập ngày 8 tháng 6 năm 2011. English shall be the official language of the Organization.
↑ Citino 2002, tr. 4: "Together with Arab and non-Arab producers, Saudi Arabia formed the Organization of Petroleum Export Countries (OPEC) to secure the best price available from the major oil corporations."
↑ Painter 2012, tr. 32: "In September 1960, after the major oil companies had twice unilaterally reduced the prices that were used to calculate how much revenue producing countries received, the oil ministers of Iran, Iraq, Kuwait, Saudi Arabia, and Venezuela formed the Organization of the Petroleum Exporting Countries […] eventually gain[ing] power over pricing in the 1970s".
