R. C. S. Trahair:Encyclopedia of Cold War espionage, spies, and secret operations. Greenwood Publishing Group, 2004, ISBN 978-0-313-31955-6, S.391 (englisch, google.at).
Sir John Stevens QPM, DL:Stevens Enquiry 3.Overview & Recommendations.Commissioner of the Metropolitan Police Service,17.April 2003,abgerufen am 17.Juli 2019.
David Isenberg:The Pitfalls of U.S. Covert Operations. In: Cato Policy Analysis. Nr.118, 7.April 1989 (archive.org): „(…) both the scope and the scale of such operations have been enormous. Paramilitary operations – which can be more accurately described as secret wars, the most extreme form of covert action – have resulted in countless deaths and immense destruction. Covert operations have become the instrument of choice for policymakers who assume that a cold war status quo is inevitable.“
