Trubachyov, Oleg, editor (1999), “*<span class="searchmatch">noktь</span>”, in Этимологический словарь славянских языков [Etymological dictionary of <span class="searchmatch">Slavic</span> languages] (in Russian), numbers...
Sudovian: nakt <span class="searchmatch">Proto</span>-<span class="searchmatch">Slavic</span>: *nòťь (see there for further descendants) Derksen, Rick (2008) “*<span class="searchmatch">nȏktь</span>”, in Etymological Dictionary of the <span class="searchmatch">Slavic</span> Inherited Lexicon...