Columbia subject headings:
Harvard subject headings:
Europe--History--1848-1849--Congresses.
Europe--History--1848-1849.
Revolutions--Europe--History--19th century
Revolutions--Europe--History--19th century--Congresses.
Princeton subject headings:
Europe--History--1848-1849--Congresses.
Europe--History--1848-1849.
Revolutions--Europe--History--19th century--Congresses.
Revolutions--Europe--History--19th century.