Columbia subject headings:
Harvard subject headings:
Bulgars (Turkic people)--History.
Bulgars (Turkic people)--Russia (Federation)--Tatarstan--History.
Volga River Region (Russia)--History.
Princeton subject headings:
Anthropological linguistics--Russia (Federation)--Tatarstan.
Bulgaro-Turkic language.
Chuvash language--History.
Inscriptions, Bulgaro-Turkic.
Tatar language--History.