Columbia subject headings:
Harvard subject headings:
Education, Bilingual--Congresses
Endangered languages--Congresses.
Language maintenance--Congresses.
Language policy--Russia (Federation)--Congresses.
Languages, Modern--Congresses.
Linguistic minorities--Congresses.
Linguistics--Congresses
Tatar language--Congresses.
Tatarstan (Russia)--Languages--Congresses.
Princeton subject headings:
Linguistic geography.