Question: Guy Pedroncini wrote the biography of this man, who ranks as France's oldest head of state?

full_context: Document 1: Anarchism in France: Anarchism in France can trace its roots to thinker Pierre-Joseph Proudhon, who grew up during the Restoration and was the first self-described anarchist. French anarchists fought in the Spanish Civil War as volunteers in the International Brigades. According to journalist Brian Doherty, "The number of people who subscribed to the anarchist movement's many publications was in the tens of thousands in France alone."
Document 2: Foreign relations of Vichy France: The Vichy regime, proclaimed by Marshal Philippe Pétain after the Fall of France in 1940 before Nazi Germany, was quickly recognized by the Allies, as well as by the USSR, until 30 June 1941 and Operation Barbarossa. However, Vichy France broke with the United Kingdom after the destruction of the French Fleet at Mers-el-Kebir. Canada maintained diplomatic relations until the occupation of Southern France (Case Anton) by Germany and Italy in November 1942.
Document 3: Vichy France: Vichy France (French: "Régime de Vichy" ) is the common name of the French State ("État français") headed by Marshal Philippe Pétain during World War II. It represented the unoccupied "Free Zone" ("zone libre") in the southern part of metropolitan France and French North Africa.
Document 4: Pierre Jeanpierre: Pierre Paul Jeanpierre (14 March 1912 – 29 May 1958) was a Frenchman, a soldier of legend in the French Foreign Legion who initially served in the French Army. He fought during World War II, the First Indochina War, the Suez Crisis and the Algerian War, where he was killed in action. Apart from a short effective time in the French resistance and days in deportation, he served exclusively since 1936 non-stop with Foreign Legion units, most notably along the entire history making of the Foreign Airborne Battalions and Regiments, and more particularly as regimental commander of the 3 time reconstituted 1st Foreign Parachute Battalion becoming the 1st Foreign Parachute Regiment (1 REP) until his demise. Uncomparable prestigious commander, colonel Jeanpierre will always remain the symbol of the 1st Foreign Parachute Regiment. Pierre advanced and placed his foreign regiment within the best assault troops amongst the French Armed Forces elite. In French Algeria, the name Jeanpierre surpassed the reputation that of Bigeard, with this nuance however: Pierre never did anything to showcase nor claim the later.
Document 5: Philippe Pétain: Henri Philippe Benoni Omer Joseph Pétain (24 April 1856 – 23 July 1951), generally known as Philippe Pétain (] ) or Marshal Pétain ("Maréchal Pétain"), was a French general who reached the distinction of Marshal of France, and later served as the Chief of State of Vichy France also known as Nationalist France or the French State "(Chef de l'État Français)", from 1940 to 1944. Pétain, who was 84 years old in 1940, ranks as France's oldest head of state. Today, he is considered the French equivalent to his contemporary Quisling in Norway. Because of his outstanding military leadership in World War I, particularly during the Battle of Verdun, Pétain was viewed as a national hero in France and was not executed. He was sometimes nicknamed "The Lion of Verdun".
Document 6: Eugénie Pétain: Eugénie Pétain (5 October 1877 - 30 January 1962) was the wife of the French military commander and political leader Philippe Pétain and was first lady of Vichy France which he ruled between 1940 and 1944.
Document 7: Maréchal, nous voilà !: "Maréchal, nous voilà !" ("Marshal, here we are!") is a French song dedicated to Marshal Philippe Pétain. Lyrics were composed by André Montagard (18881963), and music was attributed to André Montagnard and Charles Courtioux. The song was performed by André Dassary and on many official occasions in France and Algeria during Vichy France.
Document 8: Arnould Galopin: Arnould Galopin (1865, Marbeuf, Eure - 1934) was a prolific French writer with more than 50 novels to his credit. Galopin won the French Academy's Grand Prize for his "Sur le Front de Mer" (1918), a critically acclaimed novel about the Merchant Navy during World War I, and wrote several equally acclaimed novels about his experiences during the war.
Document 9: Charles de Gaulle: Charles André Joseph Marie de Gaulle (] ; 22 November 1890 – 9 November 1970) was a French general and statesman. He was the leader of Free France (1940–44) and the head of the Provisional Government of the French Republic (1944–46). In 1958, he founded the Fifth Republic and was elected as the President of France, a position he held until his resignation in 1969. He was the dominant figure of France during the Cold War era and his memory continues to influence French politics.
Document 10: Maurice Floquet: Maurice Noël Floquet (Poissons, 25 December 1894 – Montauroux, 10 November 2006) was, at age 111, France's oldest man on record and was one of the last surviving French veterans of World War I. He was, at the age of 111 years and 320 days, France's longest-lived soldier ever. Moreover, Floquet was France's oldest living man for more than four years. France's oldest person was a woman, Jeanne Calment, aged 122 years 164 days when she died, who still remains the oldest verified person ever, is more than a decade older than Floquet.
Document 11: Ardant du Picq: Charles Jean Jacques Joseph Ardant du Picq (19 October 1821 – 18 August 1870) was a French Army officer and military theorist of the mid-nineteenth century whose writings, as they were later interpreted by other theorists, had a great effect on French military theory and doctrine.
Document 12: G. C. Peden: George C. Peden is an emeritus professor of history at Stirling University, Scotland. He has written about the British Treasury; Keynesian economics; economic aspects of defence and foreign policy; the welfare state, and some recent Scottish economic history. He was born in Dundee in 1943 and educated at Grove Academy, Broughty Ferry. He worked for eight years as a sub-editor of the Dundee Evening Telegraph before becoming a mature student at Dundee University, graduating MA with first class honours in modern history in 1972. He was a postgraduate at Brasenose College, Oxford, and a research fellow at the Institute of Historical Research, London, and graduated D.Phil from Oxford in 1976, having completed his thesis under the supervision of Professor N.H. Gibbs. He was a temporary lecturer in history, Leeds University, 1976-7; lecturer in economic and social history, and then reader in economic history, Bristol University, 1977–90; and professor of history, Stirling University, 1990-2008. He was a British Academy research reader, 1987-9, and visiting fellow, All Souls College, Oxford, 1988-9, and St Catherine's College, Oxford, 2002. He is a fellow of the Royal Society of Edinburgh. According to the first version of this article, probably written by a student, Peden had a reputation for insisting on high standards of grammar in essays, perhaps reflecting his earlier career as a sub-editor. He lives in Callander, on the edge of the Scottish Highlands, and divides his time between hillwalking and research and writing.
Document 13: Guy Pedroncini: Guy Pedroncini was a French academic and military historian specialising in the First World War, and notable as the biographer of Philippe Pétain and for his work on the French army mutinies of 1917. He was born in Paris on 17 May 1924 and died on 11 July 2006, at the age of 82.
Document 14: Émile Driant: Émile Augustin Cyprien Driant (11 September 1855 – 22 February 1916) was a French writer, politician, and army officer. He was the first high-ranking casualty of the Battle of Verdun during World War I.
Document 15: Mount Pétain: Mount Pétain is located on the border of Alberta and British Columbia on the Continental Divide. It was named in 1918 after Marshal Philippe Pétain - at the time honored a war hero by Canadians as by other World War I Allies. The name was retained despite the later reversal in Pétain's reputation after his having been Head of State of Vichy France.
ground_truth: Philippe Pétain