However this does not prove that Tomokuyu existed in the 5th century, and it seems that the name of Nashiro and Koshiro were changed to Tomokuyu to adapt to a system in the Heian period.
しかしこれは、5世紀に湯沐邑があった証拠にはならず、名代・子代を平安時代の制度に呼び替えたものと思われる。