The fact that Greek ζ = Indo-European j in the words ζειαί, ζέω, ζ⋯λος, ζόρξ, ζυγόν, , and ζωρός may be regarded as fairly well established (Boisacq, Dictionnaire étymologique de la langue grecque, 307, 309, 196 sq., 311 sq.; cf. also Berneker, Slavisches etymologisches Wörterbuch, i. 447 sq.; most recent bibliography in Brugmann, Griechische Grammatik,4 151 sq.), despite the counter-arguments of Sommer (Griechische Lautstudien, 137–160; cf. also Pedersen, KZ. xxxvi. 103 sq., Meillet, Introduction à l'étude comparative des langues indo-européennes, 88).