As the preface in the Chinese poetry style composed by Michizane to "Fuso shu" (Chinese classics during the Heian period) described "my father Koreyoshi lectured on History of the Later Han Dynasty for his disciples in his Unkaku (study)," the lecture was considered to be originally given in the study Sanin-tei.
また、『扶桑集』に収められた道真の漢詩の序文にも父・是善が芸閣（書斎）で門人に『後漢書』を講じたと詠んでおり、本来は書斎の山陰亭で講義が行われていたと考えられている。