See e.g. this NDL scan here for the relevant portion of Wakan meisū: https://t.co/M4OrIYgq2E -- The same book is also the source for the kana etymographies given in the Korean manual, incl. 草 as the supposed character underlying サ. (As I said above: サ was a little tricky.) 12/ https://t.co/Bj9DpgXyZF