Columbia subject headings:
Science--Social aspects--History--19th century.
Science--Social aspects--History--20th century.
Utopias--History--19th century.
Utopias--History--20th century.
Harvard subject headings:
Science--History--Congresses
Science--Western countries--History--Congresses.
Utopias--History--Congresses.
Utopias--Western countries--History--Congresses.
Princeton subject headings:
Science--History--Congresses.
Science--Western countries--History--Congresses.
Utopias--History--Congresses.
Utopias--Western countries--History--Congresses.