1. Todd Greentree, Crossroads of Intervention: Insurgency and Counterinsurgency Lessons from Central America (Westport, CT: Praeger, 2008), 77-85.
2. General David A. Petraeus and General James F. Amos, Army Counterinsurgency Field Manual, FM3-24/MCWP 3-33.5, December 15, 2006, sec. IV, 5.
3. Elisabeth Wood, Forging Democracy from Below: Insurgent Transitions in South Africa and El Salvador (Cambridge, UK: Cambridge University Press, 2000), 52-77.
4. William D. Stanley, The Protection Racket State: Elite Politics, Military Extortion, and Civil War in El Salvador (Philadelphia: Temple University Press, 1996), 133-217.