NEW YORK, Sept. 18 (Xinhua) -- Oil prices settled mixed on Monday as oil demand is seen decreasing with refiners set to begin seasonal maintenance.

The West Texas Intermediate for October delivery increased 0.02 U.S. dollar to settle at 49.91 dollars a barrel on the New York Mercantile Exchange, while Brent crude for November delivery dipped 0.14 dollar to close at 55.48 dollars a barrel on the London ICE Futures Exchange. Enditem