"Celtic, coming from the Yamna culture, last stage of the linguistic unity, has ancient links with Eastern Indo-European, from which came Greek, Phrygian, Indo-Iranian and Slavic, and in particular with South-Carpathian languages as Thracian, Illyrian, Slavic languages of the Balkans, Ukrainian and North-Caucasian languages dating as long ago as the Vth millennium BC."