Columbia subject headings:
Harvard subject headings:
Peace movements--Europe--History.
Peace movements--History
Peace--History--Congresses.
Socialism--Europe--History
Socialist International (1889-1922). Congress (1912 : Basel, Switzerland)
Socialist International--History.
Princeton subject headings:
Peace movements--Europe--History.
Socialism--Europe--History.
Socialist International (1951- ) Congress (1912 : Basel, Switzerland)