Langdon, J. S. (1992). Byzantium's last imperial offensive in Asia Minor: The documentary evidence for and hagiographical lore about John III Ducas Vatatzes' crusade against the Turks, 1222 or 1225 to 1231. New Rochelle, N.Y.: A.D. Caratzas.
Chicago Style CitationLangdon, John Springer. Byzantium's Last Imperial Offensive in Asia Minor: The Documentary Evidence for and Hagiographical Lore About John III Ducas Vatatzes' Crusade against the Turks, 1222 or 1225 to 1231. New Rochelle, N.Y.: A.D. Caratzas, 1992.
MLA CitationLangdon, John Springer. Byzantium's Last Imperial Offensive in Asia Minor: The Documentary Evidence for and Hagiographical Lore About John III Ducas Vatatzes' Crusade against the Turks, 1222 or 1225 to 1231. New Rochelle, N.Y.: A.D. Caratzas, 1992.