Additional disclosures regarding cash flow activities are provided below.


	Nine Months Ended September 30,
(Thousands of dollars)	2011			2010
Net (increase) decrease in operating working capital other than cash and cash equivalents:
(Increase) decrease in accounts receivable	$	(314,908	)		99,628
(Increase) decrease in inventories		(31,865	)		(104,464	)
(Increase) decrease in prepaid expenses		(28,693	)		(2,045	)
(Increase) decrease in deferred income tax assets		4,797			(59,254	)
Increase (decrease) in accounts payable and accrued liabilities		185,618			412,015
Increase (decrease) in current income tax liabilities		(124,385	)		71,357

Total	$	(309,436	)		417,237


Supplementary disclosures:
Cash income taxes paid	$	608,065			419,313
Interest paid, net of amounts capitalized		18,124			17,162