MINAMOTO no Mitsuyuki and his son MINAMOTO no Chikayuki cooperated to collect 21 old manuscripts that were hereditary to correct the text of The Tale of Genji that was in total chaos at that time.
源光行とその子源親行が協力して、当時乱れに乱れていた源氏物語の本文を正すために、その当時伝来していた21部の源氏物語の古写本を集めた。