Department of State. Bureau of Diplomatic Security. Political Violence Against Americans . Washington, GPO, 1999. Colombia, pp 3-6.
Book call no.
The Contemporary Crisis in Historical Perspective , edited by Charles Bergquist and others. Wilmington, DE, SR Books, 1992. See index for references to ELN and especially pp 177-178 for history and development. Book call no. The Americas , edited by Charles F. Bahmueller.