According to "Meigetsuki" (Chronicle of the Bright Moon), the diary of FUJIWARA no Teika, 'Once there was a reliable manuscript of The Tale of Genji, which could have been called shohon (a verified text), in FUJIWARA no Teika's residence.
藤原定家の日記である『明月記』等の記述を元にすると、「藤原定家の家にはかつて「証本」と呼びうる信頼できる源氏物語の写本があった。