University Press. ; OCLC 48943301 Titsingh, Isaac. (1834). Nihon Ōdai Ichiran; ou, Annales des empereurs du Japon. Paris: Royal Asiatic Society, Oriental Translation Fund of Great Britain and Ireland. OCLC 5850691 External links National Diet Library, "The Japanese Calendar" – historical overview plus illustrative images from library's collection Japanese eras 1440s in Japan