Columbia subject headings:
Harvard subject headings:
Austria--Emigration and immigration--20th century--Congresses.
Austria--Emigration and immigration--History--20th century--Congresses.
Austria--Foreign relations--Hungary--Congresses.
Hungary--Emigration and immigration--History--20th century--Congresses.
Hungary--Foreign relations--Austria--Congresses.
Hungary--History--Revolution, 1918-1919--Congresses.
Refugees--Hungary--Congresses.
Princeton subject headings:
Austria--Emigration and immigration--History--20th century--Congresses.
Austria--Foreign relations--Hungary--Congresses.
Hungary--Emigration and immigration--History--20th century--Congresses.
Hungary--Foreign relations--Austria--Congresses.
Hungary--History--Revolution, 1918-1919--Congresses.
Refugees--Hungary--Congresses.