Paul Corner, The Fascist Party and Popular Opinion in Mussolini’s Italy (Oxford, UK: Oxford University Press, 2012).

The Ribbentrop Memoirs, ed. Alan Bullock, trans. Oliver Watson (London: Weidenfeld and Nicolson, 1954).

The Ciano Diaries, 1939–1943: The Complete, Unabridged Diaries of Count Galeazzo Ciano, Italian Minister of Foreign Affairs, ed. Hugh Gibson (New York: Doubleday, 1945).

Iris Origo, A Chill in the Air: An Italian War Diary, 1939–1940 (New York: New York Review Books, 2018), quoted in Alexander Stille, “A Chill in the Air” (book review), New York Times, September 21, 2018.

Adaam James Levin-Areddy, “Thirteen Facts About Benito Mussolini”, Mental Floss (online magazine), November 1, 2018.

Ray Moseley, Mussolini’s Shadow: The Double Life of Count Galeazzo Ciano (New Haven, CT: Yale University Press, 2000).

Edda Mussolini Ciano, My Truth (New York: Morrow, 1977).

“Hitler Still Predicting Axis Victory”, Schenectady Gazette, January 1, 1943.

“Agent Security – Gambit”, November 8, 1946, Records of the Central Intelligence Agency, 608/MG–309 (Hildegard Beetz).

Katrin Paehler, The Third Reich’s Intelligence Services: The Career of Walter Schellenberg (Cambridge, UK: Cambridge University Press, 2017).

“Hildegard Beetz”, Records of the Central Intelligence Agency, item 71.

Enrico Caviglia, I Dittatori, le Guerre e il Piccolo Re: Diario 1925–1945 (Milan, Italy: Ugo Mursia Editore, 2009), 408–409, 420–422; Alberto Pirelli, Taccuini, 1922/1943, ed. Donato Barbone (Bologna, Italy: Il Mulino, 1984).

Greg Bradsher, “A Time to Act: The Beginning of the Fritz Kolbe Story, 1900–1943”, Prologue Magazine 34, no. 1, pt. 3 (Spring 2002), National Archives of the United States.

Wilhelm Höttl, The Secret Front: The Story of Nazi Political Espionage (New York: Frederick A. Praeger, 1954).

Neal H. Petersen, From Hitler’s Doorstep: The Wartime Intelligence Reports of Allen Dulles, 1942–1945 (University Park: The Pennsylvania State University Press, 1996), 35; Paige Y. Durgin, “Framed in Death: The Historical Memory of Galeazzo Ciano”, thesis, Trinity College, 2012.

“Allen Dulles and the Compromise of OSS Codes in WW2”, Christos Military and Intelligence Corner (blog), May 23, 2012.

Francis X. Rocca, “Fascism’s Secretary of State”, The Atlantic, July 2000.