1. API (American Petroleum Institute), 2002. Petroleum HPV Testing Group; Waxes and Related Materials Category HPV Test Plan, August 6, 2002. Posted to EPA Website Aug 22, 2002; http://www.epa.gov/hpv/pubs/summaries/wxrelmat/c13902tp.pdf (accessed June 6, 2012).
2. API (American Petroleum Institute), 2003a. Petroleum HPV Testing Group; Lubricating Oil Basestocks Category HPV Test Plan, March 24, 2003. Posted to EPA Website Apr 4, 2003; (accessed June 6, 2012).
3. API (American Petroleum Institute), 2003b. Petroleum HPV Testing Group; Gas Oils Category HPV Test Plan, November 3, 2003. Posted to EPA Website Dec 16, 2003; (accessed June 6, 2012).
4. API (American Petroleum Institute), 2003c. Petroleum HPV Testing Group; Crude Oil Category HPV Test Plan, November 21, 2003. Posted to EPA Website Dec 19, 2003; (accessed June 6, 2012).
5. API (American Petroleum Institute), 2003d. Petroleum HPV Testing Group; Reclaimed Substances Category HPV Test Plan, December 15, 2003. Posted to EPA Website Jan 20, 2004; (accessed June 6, 2012).