1. Visiting Scientist Program, Scientific Analysis Section, Research Support Unit, Laboratory Division, Federal Bureau of Investigation, Huntsville, Alabama 35898, United States
2. Terrorist Explosive Device Analytical Center, Explosives Unit, Laboratory Division, Federal Bureau of Investigation, Huntsville, Alabama 35898, United States
3. Scientific Analysis Section, Research Support Unit, Laboratory Division, Federal Bureau of Investigation, Quantico, Virginia 22135, United States