Cyril Leo Heraclius, Prens Toumanoff (Rusça: Кирилл Львович Туманов; 13 Ekim 1913 – 4 Şubat 1997), Rusya doğumlu Amerikalı tarihçi ve soy bilimci, özellikle Orta Çağ Gürcistan, Ermenistan, İran ve Bizans İmparatorluğu'nun soy bilimi ve tarihi konusunda uzmandır. Çalışmaları Batı dünyasında Orta Çağ Kafkasya üzerine yapılan çalışmaları önemli ölçüde etkilemiştir.^[1] Cyril Toumanoff 1997 yılında Roma'da 83 yaşında öldü.^[1] Roma'da Campo Verano'da bulunan Malta Şövalyeleri'nin şapeline gömüldü.^[2]

• "On the Relationship between the Founder of the Empire of Trebizond and the Georgian Queen Thamar", Speculum 15 (1940).
• "Medieval Georgian Historical Literature (VIIth-XVth Centuries)", Traditio 1 (1943).
• "The Old Manuscript of the Georgian Annals: The Queen Anne Codex (QA) 1479-1495", Traditio 5 (1947)
• "The Early Bagratids. remarks in connexion with some recent publications", Le Museon 62 (1949).
• "The Fifteenth-Century Bagratids and the institution of Collegial Sovereignty in Georgia", Traditio 7 (1949–1951)
• "Christian Caucasia between Byzantium and Iran. New light from Old Sources", Traditio 10 (1954).
• (Fransızca) "La noblesse géorgienne sa genèse et sa structure", Rivista Araldica, Sett (1956).
• "Chronology of the Kings of Abasgia and Other Problems", Le Museon 69 (1956)
• "Caucasia and Byzantine Studies", Traditio 12 (1956)
• "The Bagratids of Iberia from the Eighth to the Eleventh Century", Le Museon 74 (1961)
• "The dates of the Pseudo-Moses of Chorence", Handes Amsorya 75 (1961)
• Studies in Christian Caucasian History (Georgetown University Press, 1963).
• "Armenia and Georgia", in The Cambridge Medieval History IV (1966).
• "Chronology of the Early Kings of Iberia", Traditio 25 (1969).
• The Order of Malta and the Russian Empire (Rome, 1969) with Olgerd de Sherbowitz-Wetzor.
• "The Mamikonids and the Liparitids", Armeniaca Venise (1969).
• "The Third-Century Armenian Arsacids: A chronological and Genealogical Commentary", Revue des Études Arméniennes 6 (1969): 233-281.
• "Caucasia and Byzantium", Traditio 27 (1971)
• (Fransızca) "L’Ordre de Malte dans l’Empire de Russie : Grand-Prieuré Catholique de Russie", Rivista Araldica (maggio-giugno 1973)
• (Fransızca) Manuel de généalogie et de chronologie pour l’histoire de la Caucasie chrétienne (Arménie, Géorgie, Albanie) (Rome: Aquila, 1976).
• (Fransızca) "Aransahikides ou Haykides? Derniers rois de Siounie", Handes Amsorya (1976)
• (Fransızca) Catalogue de la Noblesse titrée de l’Empire de Russie (Rome, 1982).
• (Fransızca) Les Maisons Princières Géorgiennes de l’Empire de Russie (Rome, 1983).
• "The Albanian Royal Succession", Le Museon 97 (1984).
• The Social Myth: Introduction to Byzantinism (Rome: Viella, 1984).
• "Heraclids and the Arsacids", Revue des Études Arméniennes 19 (1985).
• "Problems of Aransahikid Genealogy", Le Museon 98 (1985).
• (Fransızca) Les dynasties de la Caucasie chrétienne de l’Antiquité jusqu’au XIXe siècle ; Tables généalogiques et chronologiques, *Rome, 1990).