Rex Tillerson (C), chairman and chief executive officer of

Rex Tillerson (C), chairman and chief executive officer of Exxon Mobile shakes hands with China National Offshore Oil Corp. (CNOOC) chairman Fu Chengyu (L) as Algeria's Minister of Energy and Mines Chakib Khelil looks on at the end of a plenary session during the 19th World Petroleum Congress in Madrid, July 1, 2008. The World Petroleum Congress, which is held every three years, will last until July 3.
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