text: The oldest records of a Turkic language, the Old Turkic Orkhon inscriptions of the 7th century Göktürk khaganate, already shows characteristics of Eastern Common Turkic. For a long time, the reconstruction of Proto-Turkic relied on comparisons of Old Turkic with early sources of the Western Common Turkic branches, such as Oghuz and Kypchak, as well as the Western Oghur proper (Bulgar, Chuvash, Khazar). Because early attestation of these non-easternmost languages is much more sparse, reconstruction of Proto-Turkic still rests fundamentally on the easternmost Old Turkic of the Göktürks, however it now also includes a more comprehensive analysis of all written and spoken forms of the language.
  The Proto-Turkic language shows evidence of influence from several neighboring language groups, including Eastern Iranian, Tocharian, and Old Chinese.
  Phonology
  Consonants
  The consonant system had a two-way contrast of stop consonants (fortis vs. lenis), k, p, t vs. g, b, d. There was also an affricate consonant, ç; at least one sibilant s and sonorants m, n, ń, ŋ, r, l with a full series of nasal consonants. Some scholars additionally reconstruct the palatalized sounds ĺ and ŕ for the correspondence sets Oghuric /l/ ~ Common Turkic *š and Oghuric /r/ ~ Common Turkic *z. Most scholars, however, assume that these are the regular reflexes of Proto-Turkic *l and *r. Oghuric is thus sometimes referred to as Lir-Turkic and Common Turkic as Shaz-Turkic.