A 62 page nicely compiled pulication on Middle East Oil Pricing system has been published by the Oxford Institute of Energy Studies in May 2021. The copy is available at the link
https://ngsindia.org/wp-content/uploads/2021/05/OEF-128.pdf
You can peruse the topic MIDDLE EAST AND ASIA OIL PRICING—BENCHMARKS AND TRADING OPPORTUNITIES at page no 15