Carrels , Peter. "Going backwards: building an oil refinery in South Dakota."High Country News. 20 Nov 2008 <Going backwards: building an oil refinery in South Dakota>.
Freudenrich, Craig. "How Oil Refining Works." How Stuff Works. 20 Nov 2008 <http://science.howstuffworks.com/oil-refining2.htm>.
Global Community Monitor. 12/19/2007. Refinery Reform Campaign. 20 Nov 2008 <http://www.refineryreform.org/>.