Tất cả những nhân vật cũng như sự kiện trong cuốn sách này, theo hiểu biết của tác giả, đều có thật. Việc xây dựng cuốn sách dựa trên ý tưởng của tác giả cũng như các tư liệu đã đăng tải công khai trên báo chí và mạng Internet, có tham khảo các tài liệu sau:
1. Christopher Andrew và Vasili Mitrokhin, The Sword and The Shield (New York, Basic Books, 1999)
2. Christopher Andrew và Oleg Gordievsky, KGB: The Inside Story (New York, Harper Collins, 1990)
3. Clarence Ashley, CIA Spy Master (Gretna, Pelican Publishing Company, 2004)
4. Tennent H. Bagley, Spy Wars: Moles, Mysteries, and Deadly Games (Yale University, 2007)
5. Tennent H. Bagley, Spymaster: Startling Cold War Revelations of a Soviet KGB Chie (New York, Skyhorse Publishing, 2013)
6. John Barron, Breaking the Ring (New York, Avon Books, 1988)
7. Milton Bearden và James Risen, The Main Enemy: The Inside Story of the CIA's Final Showdown with the KGB (New York, Random House, 2003)
8. Louise Bernikow, Abel (New York, Trident Press, 1970)
9. George Blake, No Other Choice (London, Jonathan Cape, 1990)
10. Howard Blum, I pledge allegiance... (New York, Pocket Books, Simon & Schuster, 1987)
11. Sean Bourke, The Springing of George Blake (London, Cassell, 1970)
12. Victor Cherkashin và Gregory Feifer, Spy Handler: Memoir of a KGB Officer The True Story of the Man Who Recruited Robert Hanssen and Aldrich Ames (New York, Basic Books, 2005)
13. Vladimir Chikov, How the Soviet Secret Service Split the American Atom, (Novoye Vremya, 23-4-1991 và 30-4-1991).
14. Gordon Corera, The Art of Defrayal: The Secret History of MI6: Life and Death in the British Secret Service (New York, Pegasus Books, 2013)
15. John Costello, Mask Of Treachery - Spies, Lies, & Betrayal (New York, Warner Books, 1990)
16. James B. Donovan, Strangers on a Bridge: The Case of Colonel Abel and Francis Gary Powers (New York, Scribner, 2015)
17. Stephen Dorril, MI6: Inside the Covert World of Her Majesty's Secret Intelligence Service (New York, The Free Press, 2000)
18. Jeremy Duns, Dead Drop: The True Story of Oleg Penkovsky and the Cold War's Most Dangerous Operation (London, Simon & Schuster, 2014)
19. Edward Jay Epstein, Deception: The Invisible War Between the KGB and the CIA (New York, Simon & Schuster, 1989)
20. Oleg Gordievsky, Next Stop Execution (London, Macmillan, 1995)
21. Sandra Grimes và Jeanne Vertefeuille, Circle of Treason: A CIA Account of Traitor Aldrich Ames and the Men He Betrayed (Annapolis, Maryland, Naval Institute Press, 2013)
22. David E. Hofiman, The Billion Dollar Spy: A True Story of Cold War Espionage and Betrayal (New York, Doubleday, Penguin Random House, 2015)
23. Robert W. Hunter, Spy Hunter: Inside the FBI Investigation of the Walker Espionage Case (Maryland, Naval Institute Press, Annapolis, 1999)
24. H. Montgomery Hyde, The Atom Bomb Spies (Harford Productions Ltd, 1980)
25. Oleg Kalugin, Spymaster (New York, Basic Books, 2009)
26. Ronald Kessler, Escape from the CIA: How the CIA Won and Lost the Most Important KGB Spy Ever to Defect to the U. S. (New York, Pocket Star Book, Simon & Schuster, 1991)
27. Phillip Knightley, The Master Spy: The Story of Kim Philby (New York, Alfred A. Knopf, 1989)
28. Robert J. Lamphere và Tom Shachtman, The FBI - KGB War (New York, Berkley Books, 1986)
29. Peter Maas, Killer Spy (New York, Warner Book, 1996)
30. Fitzroy Maclean, Nine Lives (New York, Tauris Parke Paperbacks, 2008)
31. Ben Macintyre, Spy Among Friends (London, Bloomsbury, 2014)
32. H. Montgomery Hyde, George Blake - Superspy (London, Constable, 1987)
33. David E. Murphy, Sergei A. Kondrashev, George Bailey, Battle Ground Berlin (New Haven & London, Yale University Press, 1997)
34. Bruce Page, David Leich, Phillip Knightley, ThePhilby Conspiracy (Toronto, Fontana Books, 1968)
35. Oleg Penkovskiy, The Penkovskiy Papers (New York, Doubleday & Company, 1965)
36. Richard Rhodes, Dark Sun (New York, Simon & Schuster, 1995)
37. Jeffrey T. Richelson, A Century of Spies (New York, Oxford University Press, 1995)
38. Mike Rossiter, The Spy Who Changed the World (London, Headline Publishing Group, 2014)
39. Jerrold L. Schecter và Peter s. Deriabin, The Spy Who Save the World (New York, Macmillan, 1992)
40. David Stafford, Spies Beneath Berlin (Woodstock & New York, The Overlook Press, 2002)
41. Richard c. s. Trahair và Robert L. Miller, Encyclopedia of Cold War Espionage (New York, Enigma Books, 2012)
42. Ernest Volkman, Espionage - The Greatest Spy Operations of the 2ơh Century (John Wiley & Sons, Inc., 1995)
43. Tim Weiner, David Johnston và Neil A. Lewis, Betrayal (New York, Random House, 1995)
44. Tim Weiner, Legacy of Ashes (New York, Anchor Books, 2008)
45. Nigel West, The Circus (New York, Stem and Day, 1984)
46. Nigel West, The Illegals (London, Holder and Stoughton, 1993)
47. Rebecca West, The New Meaning Of Treason (Harmondsworth, Penguin Books, 1965)
48. Giles Whittell, Bridge of Spies (Simon & Schuster, 2011)
49. David Wise và Thomas B. Ross, The U-2 Affair (New York, Batam Book, 1962)
50. Peter Wright, Spy Catcher (Australia, William Heinemann, 1988)
