Historical secret police organizations

• Organismo Coordinador de Actividades Anti-Subversivas (Anti-Subversive Activities Co-ordination Organization)

Sources

1. World Police Encyclopedia, ed. by Dilip K. Das & Michael Palmiotto. by Taylor & Francis. 2004,
2. World Encyclopedia of Police Forces and Correctional Systems, 2nd. edition, Gale., 2006
3. Sullivan, Larry E. et al. Encyclopedia of Law Enforcement. Thousand Oaks: Sage Publications, 2005.