We appreciate the large community of photographers who have licensed their works under the Creative Commons license. Photos used on our site include:

tubgurnard on Flickr
Creative Commons License, some rights reserved.

http://commons.wikimedia.org/wiki/Image:Celestia_earth2.jpg

http://commons.wikimedia.org/wiki/Image:Line_at_a_gas_station%2C_June_15...

http://commons.wikimedia.org/wiki/Image:Imported_Crude_Oil_as_a_Percent_...

http://commons.wikimedia.org/wiki/Image:2006-10-24_oil-puddle.jpg

http://commons.wikimedia.org/wiki/Image:Sheetz_Sign.jpg