Columbia subject headings:
Voluntarism--Germany--History--20th century.
Voluntarism--Great Britain--History--20th century.
Young volunteers--Germany--History--20th century.
Young volunteers--Great Britain--History--20th century.
Harvard subject headings:
Voluntarism--Germany--History--20th century.
Voluntarism--Great Britain--History--20th century.
Young volunteers--Germany--History--20th century.
Young volunteers--Great Britain--History--20th century.
Princeton subject headings:
Voluntarism--Germany--History--20th century.
Voluntarism--Great Britain--History--20th century.
Young volunteers--Germany--History--20th century.
Young volunteers--Great Britain--History--20th century.