 Although Gabdulkhay Akhatov was a Volga Tatar, he immersed into studying of the phonetic peculiarities of Siberian Tatar language of the indigenous population of Siberia, the Siberian Tatars.In his classic fundamental research work "The Dialect of the West Siberian Tatars" (1963) Akhatov wrote about Tobol-Irtysh Siberian Tatars, a western group of Siberian Tatars, who are indigenous to the Omsk and Tyumen Oblasts.After a comprehensive integrated analysis of the phonetic system, the lexical composition and the grammatical structure, the scientist concluded that the language of the Siberian Tatars was a separate language from the beginning, and it is one of the most ancient Turkic languages.