1. American Petroleum Institute (API), 2006. Toxics Release Inventory, p. 3. (last referenced: February 2014).
2. American Petroleum Institute (API), 2008. Gasoline Blending Streams Category Assessment. Submitted by the Petroleum HPV Testing Group, Consortium Registration #1100997, pp. 8–9, August 2008.
3. American Petroleum Institute (API), 2010. Compilation of Emission Estimation Methods for Calculating Air Emissions Under the U.S. EPA Toxics Release Inventory (TRI), March 2010.
4. American Petroleum Institute (API), 2013. Statistics Department, Monthly Statistical Report, Volume 37, No. 12. Available via IHS Global at www.global.ihs.com, p. 1, December 2013. (last referenced: February 2014).
5. California Code of Regulations, 2013. Title 24, § 2201 et seq.