Further, there are opinions that the 'common noun' which is thought to be the generic term for several books or documents that satisfy fixed conditions, such as the "Teiki," which every family was thought to have, and the "Teio Honki" (Chronicle of Emperors) which existing contents were supposed to be different, and the 'proper noun' which is thought to describe specific books that are complied at a specific point of time called "Teiki no Hitsugi" should be clearly distinguished.
また、諸家がそれぞれ持っているとされる『帝紀』や内容の異なるものが存在するとされる『帝王本紀』のような一定の条件を満たす複数の書物ないしは文書の総称であると考えられる「普通名詞」と、『帝王の日嗣』といった特定の時点で編纂された特定の書物を示すと見られる「固有名詞」とは明確に区別するべきであるとする見解もある。