1.   The leaded petrol Market is shrinking so fast that some major petroleum companies have discontinued refining leaded petrol.

2.   Micropalaeontological studies on recovered core samples have been used for stratigraphical studies on behalf of petroleum exploration companies.

3.   Although the field is run by Occidental and Royal Dutch Shell Group, the Colombian state petroleum company Ecopetrol is a partner in their operations.

4.   American petroleum companies have shifted their reliance from the gulf to nations in the Western Hemisphere.

5.   And British petroleum companies were extracting oil in Iran, Iraq, Kuwait, Qatar and Egypt.

6.   And many Democrats called for an investigation of possible price gouging by the oil industry, suggesting that petroleum companies had deliberately created a gasoline shortage.

7.   And unlike other big Russian petroleum companies, it pledges to make public the identities of its major shareholders, probably next year.

8.   At various times, the company has owned petroleum companies and textile makers, and is considered complex both structurally and financially.

9.   A subsidiary of the Turkish state-owned petroleum company announced Friday that it had signed a deal with the Iraqi government of Saddam Hussein to drill for oil.