Columbia subject headings:
Aḥmad, king of Yemen, 1891-1962.
Yemen (Republic)--History--20th century.
Harvard subject headings:
Aḥmad, king of Yemen, 1891-1962.
Yemen (Republic)--History.
Princeton subject headings:
Ahmad, Imam of Yemen, 1893-1962.
Yemen (Republic)--History--20th century.