Columbia subject headings:
Labor--United States--1914-1918.
World War, 1914-1918--Economic aspects.
World War, 1914-1918.
Harvard subject headings:
Labor--United States
Working class--United States
World War, 1914-1918
World War, 1914-1918--Economic aspects
Princeton subject headings:
Labor--United States--History--20th century.
World War, 1914-1918--Economic aspects.
World War, 1914-1918.