Columbia subject headings:
Bulgars (Turkic people)--Europe, Eastern--Congresses.
Ethnology--Europe, Eastern--Congresses.
Europe, Eastern--Antiquities--Congresses.
Finno-Ugrians--Europe, Eastern--Congresses.
Harvard subject headings:
Bulgars (Turkic people)
Europe, Eastern--Antiquities.
Finno-Ugrians.
Princeton subject headings: