Комментарии:EAS 77, KW 280, Владимирцов 187, 369, Poppe 39, Дыбо 317, Лексика 253. Despite Щербак 1997, 125 and Doerfer MT 77, Rozycki 164 borrowing in Mong. from Turk. and TM from Mong. is excluded. TM has a regular loss of *-d- before -r-, with subsequent vowel contraction; Jpn. also reflects a contraction: *ni̯údurgi > *nuj(u)ki- > *ni(n)ki-. It is interesting to note that all subgroups reflex the form with *-rgi; this means that Mong. nidur(a)-, nidu-či- 'to strike with the fist' may be analogical back-formations (or else the most archaic forms reflecting suffixless *ni̯údu).