Columbia subject headings:
Harvard subject headings:
Europe--Emigration and immigration--Congresses.
Europe--History, Military--Congresses.
Migration, Internal--Europe--Congresses.
Military art and science--Europe--History--Congresses.
War and society--Europe--History--Congresses.
Princeton subject headings:
Europe--Emigration and immigration--Congresses.
Europe--History, Military--Congresses.
Migration, Internal--Europe--Congresses.
Military art and science--Europe--History--Congresses.
War and society--Europe--History--Congresses.