Columbia subject headings:
Harvard subject headings:
Christianity--Russia--Congresses.
Kievan Rus--Church history--Congresses.
Millennium of Christianity in Kievan Rus, 988-1988--Congresses.
Orthodox Eastern Church--Kievan Rus--History--Congresses.
Orthodox Eastern Church--Soviet Union--History--Congresses.
Russkai︠a︡ pravoslavnai︠a︡ t︠s︡erkovʹ--History--Congresses.
Soviet Union--Church history--Congresses.
Princeton subject headings:
Christianity--Russia--History--Congresses.
Christianity--Ukraine--History--Congresses.
Russia--Church history--Congresses.
Ukraine--Church history--Congresses.