Комментарии:Räsänen 1955, 18:3, 19 (Turk.-Tung.), ОСНЯ 1, 298-299, Лексика 186, Robbeets 2000, 108; TMN 3, 660 ("...der ev. Vergleich zweifelhaft..."). The Japanese form goes back to a suffixed *kuńe-gV (cf. the TM and Kor. forms); the vowel, however, is quite irregular - which may be due to contraction (cf. a very similar case in PJ *ka 'day' < PA *gi̯òjńu).
