Columbia subject headings:
Communism--Soviet Union--Congresses.
Proletariĭ (Vyborg, Russia)--Congresses.
Harvard subject headings:
Communism--Soviet Union--Congresses
Proletariĭ (Vyborg, R.S.F.S.R.)--Congresses.
Princeton subject headings:
Communism--Soviet Union--Congresses.
Proletariĭ (Vyborg, R.S.F.S.R.)--Congresses.