Isaac Titsingh, "Keitei" em Annales des empereurs du japon, (em francês) Paris: Royal Asiatic Society, Oriental Translation Fund of Great Britain and Ireland p. 31 OCLC5850691.
William George Aston, (1896). Nihongi: Chronicles of Japan from the Earliest Times to A.D. 697 (em inglês) London: Kegan Paul, Trench, Trubner p. 398 - 410. OCLC 448337491
JienThe Future and the Past: A Translation and Study of the Gukanshō, an Interpretative History of Japan Written in 1219 (em inglês), University of California Press, 1979 pp. 260 ISBN 9780520034600
William George Aston, (1896). Nihongi: Chronicles of Japan from the Earliest Times to A.D. 697 (em inglês) London: Kegan Paul, Trench, Trubner p. 410 - 415. OCLC 448337491
Isaac Titsingh, "Keitei" em Annales des empereurs du japon, (em francês) Paris: Royal Asiatic Society, Oriental Translation Fund of Great Britain and Ireland p. 31 OCLC5850691.