Columbia subject headings:
Censorship--Europe, Central--History--Congresses.
Censorship--Europe, Eastern--History--Congresses.
Literature publishing--History--Congresses.
Publishers and publishing--History--Congresses.
Underground literature--History and criticism--Congresses.
Harvard subject headings:
Censorship--Europe, Central--History--Congresses.
Censorship--Europe, Eastern--History--Congresses.
Literature publishing--History--Congresses.
Publishers and publishing--History--Congresses.
Underground literature--History and criticism--Congresses.
Princeton subject headings: