Nihon Koki (Later Chronicle of Japan) - covering the period from Emperor Kammu to Emperor Junna (792-833) in forty volumes (however, thirty volumes were lost and only ten volumes exist.)
日本後紀-桓武天皇から淳和天皇まで（792年-833年）を扱う、40巻（但し3/4が失われ10巻分のみ現存）。