↑ 1.01.1De Vaan, Michiel (2008) Etymological Dictionary of Latin and the other Italic Languages (Leiden Indo-European Etymological Dictionary Series; 7)[1], Leiden, Boston: Brill, →ISBN
^ Lua error in Module:parameters at line 376: Parameter 1 should be a valid language or etymology language code; the value "1981" is not valid. See WT:LOL and WT:LOL/E.
^ Guus Kroonen (2013) “*airi”, in Alexander Lubotsky, editor, Etymological Dictionary of Proto-Germanic (Leiden Indo-European Etymological Dictionary Series; 11)[3], Leiden, Boston: Brill, →ISBN, page 12